chore(ci): consolidate Gitea CI (#47)

## Summary

- consolidate vet, tests, lint, smoke, and cross-build into one pull-request-only job
- keep binary releases strictly v-tag-only with release-only write permission
- retain wrapper synchronization only for canonical wrapper changes on main
- pin actions and enforce exact trigger contracts

## Verification

- nix develop --command make check
- trigger mutation contract
- 28-workflow cross-repository actionlint audit

Generated with Claude CodeReviewed-on: #47

Co-authored-by: vickydotbat <vickydotbat@tutamail.com>

.gitea/workflows/build-binaries.yml

@@ -1,25 +1,22 @@
-# Cross-platform Crucible binaries (D7 trigger standard):
-#   PR / push main -> cross-build ALL targets to prove they compile (no publish)
-#   tag v*         -> build all targets + SHA256SUMS, upload to the Gitea release
+# Cross-platform Crucible release binaries: a v* tag builds all targets,
+# then uploads them, SHA256SUMS, and the canonical wrappers to its Gitea release.
 # Crucible is pure Go (CGO_ENABLED=0), so cross-compiling is a fast loop.
 name: build-binaries
 
 on:
-  pull_request:
   push:
-    branches: [main]
     tags: ['v*']
-    paths-ignore:
-      - "docs/**"
-      - "README.md"
-      - "AGENTS.md"
-      - "LICENSE"
+
+permissions:
+  code: read
+  releases: write
 
 jobs:
   build-binaries:
     runs-on: nix-docker
+    timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with: { fetch-depth: 0 }
 
       - name: Cross-build all targets
@@ -45,9 +42,8 @@ jobs:
           '
 
       - name: Upload to Gitea release
-        if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
         env:
-          TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          TOKEN: ${{ secrets.GITEA_TOKEN }}
           TAG: ${{ github.ref_name }}
           REPO: ${{ github.repository }}
           SERVER: ${{ github.server_url }}