refactor: CI optimization, logging improvements, and codebase formatting (#456)

* fix(db): remove unique constraint on folder to support multi-channel agents

* ci: implement automated skill drift detection and self-healing PRs

* fix: align registration logic with Gavriel's feedback and fix build/test issues from Daniel Mi

* style: conform to prettier standards for CI validation

* test: fix branch naming inconsistency in CI (master vs main)

* fix(ci): robust module resolution by removing file extensions in scripts

* refactor(ci): simplify skill validation by removing redundant combination tests

* style: conform skills-engine to prettier, unify logging in index.ts and cleanup unused imports

* refactor: extract multi-channel DB changes to separate branch

Move channel column, folder suffix logic, and related migrations
to feat/multi-channel-db-v2 for independent review. This PR now
contains only CI/CD optimizations, Prettier formatting, and
logging improvements.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/skill-drift.yml

@@ -0,0 +1,102 @@
+name: Skill Drift Detection
+
+# Runs after every push to main that touches source files.
+# Validates every skill can still be cleanly applied, type-checked, and tested.
+# If a skill drifts, attempts auto-fix via three-way merge of modify/ files,
+# then opens a PR with the result (auto-fixed or with conflict markers).
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'src/**'
+      - 'container/**'
+      - 'package.json'
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  # ── Step 1: Check all skills against current main ─────────────────────
+  validate:
+    runs-on: ubuntu-latest
+    outputs:
+      drifted: ${{ steps.check.outputs.drifted }}
+      drifted_skills: ${{ steps.check.outputs.drifted_skills }}
+      results: ${{ steps.check.outputs.results }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: npm
+      - run: npm ci
+
+      - name: Validate all skills against main
+        id: check
+        run: npx tsx scripts/validate-all-skills.ts
+        continue-on-error: true
+
+  # ── Step 2: Auto-fix and create PR ────────────────────────────────────
+  fix-drift:
+    needs: validate
+    if: needs.validate.outputs.drifted == 'true'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/create-github-app-token@v1
+        id: app-token
+        with:
+          app-id: ${{ secrets.APP_ID }}
+          private-key: ${{ secrets.APP_PRIVATE_KEY }}
+
+      - uses: actions/checkout@v4
+        with:
+          token: ${{ steps.app-token.outputs.token }}
+          fetch-depth: 0
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: npm
+      - run: npm ci
+
+      - name: Attempt auto-fix via three-way merge
+        id: fix
+        run: |
+          SKILLS=$(echo '${{ needs.validate.outputs.drifted_skills }}' | jq -r '.[]')
+          npx tsx scripts/fix-skill-drift.ts $SKILLS
+
+      - name: Create pull request
+        uses: peter-evans/create-pull-request@v7
+        with:
+          token: ${{ steps.app-token.outputs.token }}
+          branch: ci/fix-skill-drift
+          delete-branch: true
+          title: 'fix(skills): auto-update drifted skills'
+          body: |
+            ## Skill Drift Detected
+
+            A push to `main` (${{ github.sha }}) changed source files that caused
+            the following skills to fail validation:
+
+            **Drifted:** ${{ needs.validate.outputs.drifted_skills }}
+
+            ### Auto-fix results
+
+            ${{ steps.fix.outputs.summary }}
+
+            ### What to do
+
+            1. Review the changes to `.claude/skills/*/modify/` files
+            2. If there are conflict markers (`<<<<<<<`), resolve them
+            3. CI will run typecheck + tests on this PR automatically
+            4. Merge when green
+
+            ---
+            *Auto-generated by [skill-drift CI](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }})*
+          labels: skill-drift,automated
+          commit-message: 'fix(skills): auto-update drifted skill modify/ files'