docs: adopt workspace-wide agent standards and retire sow-docs

Scaffold the per-repo configuration the engineering skills expect, and put
the three-way split of work into standing law:

- Live work -> wayfinder maps + Gitea issues (closeable, assignable,
  queryable).
- Settled decisions -> ADR files in docs/adr/ (immutable, findable, never
  closed).
- Standing law -> DOCTRINE.md / AGENTS.md / CONTEXT.md.

Adds docs/agents/{issue-tracker,triage-labels,domain}.md and an
"Agent skills" section in AGENTS.md. The tracker doc records Gitea via the
tea CLI, the wayfinder map/ticket/blocking operations, and the rule that
issues follow ownership: file work in the repo that owns it, not the one you
happen to be standing in.

ADR-0001 (markdown is reference, law, or an ADR - nothing else) is adopted
from sow-codebase so the rule is local to every repo.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

AGENTS.md

@@ -522,3 +522,21 @@ area with the tileset and walk-test. Much faster than pack→reload; pack the
 
 _Verify specifics against the wiki before relying on them; correct this file when
 you find drift._
+
+## Agent skills
+
+### Issue tracker
+
+Issues live in Gitea at git.westgate.pw (`ShadowsOverWestgate/sow-module-tilesets`), managed with the `tea` CLI. Issues follow ownership — file work in the repo that owns it, not the one you happen to be standing in. See `docs/agents/issue-tracker.md`.
+
+### Triage labels
+
+Default label vocabulary (`needs-triage`, `needs-info`, `ready-for-agent`, `ready-for-human`, `wontfix`). See `docs/agents/triage-labels.md`.
+
+### Domain docs
+
+Single-context: `CONTEXT.md` at the repo root plus `docs/adr/`. See `docs/agents/domain.md`.
+
+### Where work lives
+
+Markdown here is **reference, law, or an ADR — nothing else** (`sow-codebase` ADR-0001). Live work -> wayfinder maps + Gitea issues (closeable, assignable, queryable). Settled decisions -> ADR files in `docs/adr/` (immutable, never closed, only superseded). Standing law -> `DOCTRINE.md` / `AGENTS.md` / `CONTEXT.md`. Current-state reference -> docs describing what the code does now. Everything else — plans, specs, concepts, handoffs, trackers — is process: it belongs in a Gitea issue, not a file. Harvest unfinished intent to an issue before deleting a process doc. `sow-docs` is deprecated and read-only.