docs: extend assets builder spec with mdl/dupe integrity tools

Fold check-ascii-mdl, fix-mdl-model-names, check-duplicate-names, and
clean-duplicate-names out of sow-assets-manifest into `crucible assets`
(seven commands total), via a shared internal/assets/mdl port of
mdl-name-lib.sh + mdl-scan.awk. Consumer keeps the awk libs for import.sh's
hot-path gate; moving import.sh into `crucible depot` is a decomposed
follow-up spec.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/superpowers/specs/2026-07-12-crucible-assets-builder-design.md

@@ -5,12 +5,19 @@ Status: approved, pre-implementation
 
 ## Goal
 
-Fold three NWN:EE asset tools out of the standalone Python toolkit
-(`nwnee-asset-processing`) and into Crucible as a new self-contained builder,
-`crucible assets`. The Python scripts are references only; they are broken as-is
-and carry a heavy config/staging/report layer that we drop.
+Fold the NWN:EE asset tools out of two standalone toolkits into Crucible as a
+new self-contained builder, `crucible assets`:
 
-Three commands:
+- from the Python toolkit (`nwnee-asset-processing`) — model compile, texture
+  convert, texture upscale. Those scripts are references only; broken as-is and
+  carrying a heavy config/staging/report layer that we drop.
+- from `sow-assets-manifest/scripts/` — the model-name and duplicate-name
+  integrity tools (`check-ascii-mdl.sh`, `fix-mdl-model-names.sh`,
+  `check-duplicate-names.sh`, `clean-duplicate-names.sh`). These are ported into
+  Go and the shell drivers removed; `sow-assets-manifest` calls
+  `./crucible.sh assets …` through its bootstrap wrapper instead.
+
+Seven commands:
 
 - `crucible assets compile` — compile every ASCII `.mdl` in a directory to
   binary, in place.
@@ -19,6 +26,14 @@ Three commands:
   always upside-down relative to its source.
 - `crucible assets upscale` — upscale every texture in a directory through
   whatever upscaling backend is installed.
+- `crucible assets check-mdl` — report uncompiled ASCII `.mdl` files and
+  model-name mismatches (read-only).
+- `crucible assets fix-mdl` — lowercase `.mdl` filenames and rewrite ASCII
+  model/root names to match each file's stem.
+- `crucible assets check-dupes` — report runtime-name (basename) collisions in
+  directories, or hak-scoped collisions across `assets/*.yml` manifests.
+- `crucible assets clean-dupes` — delete files from a "clean" tree whose
+  basename collides with anything in a "primary" tree.
 
 ## Principles
 
@@ -42,19 +57,21 @@ A new self-contained builder that follows the existing `depot` pattern exactly
 
 - `internal/assets/run.go` — `func Run(args []string, stdout, stderr io.Writer,
   getenv func(string) string) int`. Parses the subcommand
-  (`compile|convert|upscale`) and dispatches. Returns a sysexits-style code.
+  (`compile|convert|upscale|check-mdl|fix-mdl|check-dupes|clean-dupes`) and
+  dispatches. Returns a sysexits-style code.
 - `internal/assets/` — one file per command plus small shared helpers
   (recursion/file-selection, external-command runner, backend discovery).
 - `cmd/crucible-assets/main.go` — one-line shim:
   `func main() { os.Exit(dispatch.RunBuilder("assets", os.Args[1:])) }`.
 - `internal/dispatch`:
-  - one `Registry` entry for `assets` (`Wired: true`) listing the three
+  - one `Registry` entry for `assets` (`Wired: true`) listing the seven
     commands with `Usage`/`Options`;
   - extend the direct-delegate branch that today reads
     `if b.Name == "depot" && b.Wired` so `assets` also routes to
     `assets.Run(...)` instead of the legacy `app.Run`.
-- `docs/command-surface.md` — three visible-command rows.
-- `wrappers/consumers.txt` / wrappers are unchanged (no new consumer).
+- `docs/command-surface.md` — seven visible-command rows.
+- `wrappers/consumers.txt` / wrappers are unchanged (no new consumer; the
+  consumers listed already vendor the wrapper).
 
 ### Shared helpers (`internal/assets`)
 
@@ -68,6 +85,28 @@ A new self-contained builder that follows the existing `depot` pattern exactly
   first path that exists from a supplied list of candidates. Used by every
   backend discovery.
 
+### Shared MDL name module (`internal/assets/mdl`)
+
+A pure-Go port of `mdl-name-lib.sh` + `mdl-scan.awk`, no external tools. One
+place three commands share (`compile`'s pre-check, `check-mdl`, `fix-mdl`):
+
+- `IsASCII(path)` — NUL in the first 256 bytes → binary; else the leading
+  keyword must be `#`/`newmodel`/`node`/`setsupermodel`. Mirrors `mdl_is_ascii`.
+- `ExpectedName(path)` — the file stem (sans `.mdl`).
+- `CheckNames(path) []Mismatch` — for an ASCII model, report header-token
+  mismatches (`newmodel`, `setsupermodel`, `beginmodelgeom`, `endmodelgeom`,
+  `donemodel`, `newanim`, `doneanim` — case-insensitive vs the stem) and the
+  geometry **base node** mismatch (the node inside `beginmodelgeom` whose parent
+  is `null`; empty if none). Mirrors `mdl_check_model_name` + `mdl_base_name`.
+- `FixNames(in) (out []byte, changed bool)` — rewrite only the model identity:
+  the header tokens above, plus the base node's declaration / any `parent` /
+  `animroot` pointing at the *old* base name → the expected name. Animation bone
+  names and supermodel animroots are left untouched so inheritance keeps working.
+  Mirrors `mdl_fix_model_name` byte-for-byte in intent.
+
+Detection must stay identical to the awk classifier so behavior does not drift
+while `import.sh` still runs the awk version (see Consumer migration).
+
 ## `crucible assets compile <dir>…`
 
 Usage: `crucible assets compile [--nwn <install>] [--non-recursive] <dir>…`
@@ -108,9 +147,11 @@ engine log (`~/.local/share/Neverwinter Nights/logs/nwengineLog.txt`) as
 advisory diagnostics.
 
 Dropped vs reference: internal-name-mismatch pre-checks and the
-`Model Names Differ` fail rule are kept (cheap, prevents silent wrong output);
-the discard-manifest, dry-run/report layer, and `processing/in|out` staging are
-dropped.
+`Model Names Differ` fail rule are kept (cheap, prevents silent wrong output),
+using the shared `internal/assets/mdl` module — `compile` aborts a model whose
+names differ and tells the user to run `crucible assets fix-mdl`. It does **not**
+auto-fix (kept separate, by decision). The discard-manifest, dry-run/report
+layer, and `processing/in|out` staging are dropped.
 
 ## `crucible assets convert <dir>…`
 
@@ -165,12 +206,109 @@ Recursively upscale textures in place.
 Dropped vs reference: min-dimension small-texture staging, the separate
 `--dds-backend` plumbing (it reuses convert), configured backend-path table.
 
+## `crucible assets check-mdl <path>…`
+
+Port of `check-ascii-mdl.sh`. Read-only. Each `<path>` is a file or a directory
+(recursed for `*.mdl`). For every model, using `internal/assets/mdl`:
+
+- report an **uncompiled ASCII** `.mdl` (a binary/compiled one is fine, skipped);
+- report every model-name mismatch (header tokens and geometry base node) with
+  file, line, the offending token, and the expected stem.
+
+Exit non-zero if any ASCII model or mismatch is found; zero and an `OK` line
+otherwise. No mutation.
+
+## `crucible assets fix-mdl [--dry-run] <path>…`
+
+Port of `fix-mdl-model-names.sh`. For each `*.mdl` under the paths:
+
+1. **Lowercase the filename** if it is not already lowercase (`mv`; abort that
+   file on a case-collision with an existing target).
+2. For ASCII models with a name mismatch, rewrite the model identity in place
+   via `mdl.FixNames` (binary models are skipped — the engine owns those).
+
+`--dry-run` reports every "would lowercase" / "would fix" without touching disk.
+Prints a per-file log and a final `no broken mdl model names found` when clean.
+
+Selection optimization from the reference is preserved: a file is a fix
+candidate only if it needs a content fix (name mismatch) or a filename
+lowercase, so the expensive per-file read/rewrite runs only on the few that
+matter, not the whole tree.
+
+## `crucible assets check-dupes [--manifests] <dir>…`
+
+Port of `check-duplicate-names.sh`. Read-only. NWN packs hak entries by
+basename, not path, so files at different paths with the same basename
+(case-insensitively) silently clobber on pack. This flags them.
+
+- Directory mode (default): across all `<dir>` args, report any two files whose
+  lowercased basename matches.
+- `--manifests`: additionally read every `assets/*.yml` in the current repo and
+  report basename collisions **within the same hak** (`.assets[].path` grouped
+  by `.assets[].hak`), reusing Crucible's existing `gopkg.in/yaml.v3` parsing.
+  Requires no external `yq`.
+
+Exit non-zero if any collision is found.
+
+## `crucible assets clean-dupes [--dry-run] <primary> <clean>`
+
+Port of `clean-duplicate-names.sh`. Deletes files from the `<clean>` tree whose
+basename collides (case-insensitively) with any file in the `<primary>` tree.
+Mutates only `<clean>`. Same rule as `check-dupes` directory mode, but resolves
+the collision by removal instead of reporting.
+
+- Refuses to run if `<primary>` and `<clean>` overlap (either contains the
+  other), matching the script's guard.
+- `--dry-run` reports every "would delete" without removing.
+
+Exit zero on success with a count of removed (or would-remove) files.
+
+## Consumer migration (`sow-assets-manifest`)
+
+`sow-assets-manifest` already ships the `crucible` bootstrap wrapper
+(`crucible.sh`) and uses `crucible depot` from its Makefile, so it resolves a
+released `crucible` with zero extra setup.
+
+- **Delete** the four folded driver scripts: `scripts/check-ascii-mdl.sh`,
+  `scripts/fix-mdl-model-names.sh`, `scripts/check-duplicate-names.sh`,
+  `scripts/clean-duplicate-names.sh`.
+- **Repoint** the Makefile targets to the wrapper:
+  - `check-mdl` → `./crucible.sh assets check-mdl …`
+  - `fix-mdl` → `./crucible.sh assets fix-mdl [--dry-run] …`
+  - `check-dupes` → `./crucible.sh assets check-dupes …` and
+    `./crucible.sh assets check-dupes --manifests`
+  - `clean-dupes` → `./crucible.sh assets clean-dupes [--dry-run] <PRIMARY> <CLEAN>`
+  - the `haks` target's `check-duplicate-names.sh --manifests` guard →
+    `./crucible.sh assets check-dupes --manifests`
+- **Keep for now:** `scripts/mdl-scan.awk` and `scripts/mdl-name-lib.sh`. They
+  are still sourced by `import.sh` for its batched pre-import gate (~28× faster
+  than per-file, on a hot path). They retire in the follow-up below. Because
+  both the awk classifier and the Go `mdl` module must agree, the port keeps
+  detection byte-for-byte identical (a shared fixture set checks this).
+
+Nothing in `sow-assets-manifest` is committed by this project's plan except the
+script deletions and Makefile edits; that repo's change lands as its own commit
+once the new `crucible` release with `assets` is available.
+
+## Out of scope — follow-up spec
+
+Moving the **depot-interacting pipeline** (`import.sh`, `sync-assets.sh`,
+`export.sh`, and the inline mdl gate) into `crucible depot` is a separate
+project with its own spec. When `import.sh` becomes `crucible depot import`, its
+gate uses the in-process `internal/assets/mdl` module and
+`scripts/mdl-scan.awk` + `scripts/mdl-name-lib.sh` are deleted. This spec
+deliberately stops at the standalone integrity tools to keep one focused plan.
+
 ## Error handling
 
 - Missing external tool (engine, `magick`, upscaler) → non-zero exit, message
-  names the tool and how to get it. Never a faked artifact.
+  names the tool and how to get it. Never a faked artifact. The pure-Go
+  integrity commands (`check-mdl`, `fix-mdl`, `check-dupes`, `clean-dupes`) need
+  no external tool.
 - Per-file failures are collected and printed as a summary line at the end; the
   command exits non-zero if any file failed but still processes the rest.
+- Report commands (`check-mdl`, `check-dupes`) exit non-zero when they *find*
+  problems — that is their contract as CI/pre-import gates, not a tool error.
 - Unknown subcommand / bad flags → usage error, exit 64.
 
 ## Testing
@@ -184,6 +322,14 @@ Go tests in `internal/assets`:
 - one real convert round-trip using `magick` (present in the dev shell):
   encode a small PNG to DDS and back, asserting the pixels are vertically
   flipped after a single conversion and restored after the round trip.
+- `internal/assets/mdl`: table-driven fixtures — ASCII vs binary detection,
+  each header-token mismatch, the base-node mismatch, and `FixNames` producing
+  a model that then passes `CheckNames`. A parity fixture set shared in intent
+  with `mdl-scan.awk` so the Go port and the still-present awk agree.
+- `check-dupes`/`clean-dupes`: temp trees asserting basename-collision
+  detection (case-insensitive), the `--manifests` hak-scoped path against a
+  small `assets/*.yml` fixture, the overlap guard, and `--dry-run` mutating
+  nothing.
 
 External engine/upscaler calls are exercised through the `run` indirection with
 a stub in tests; they are not invoked for real in CI.