ci: summarize static checks and retain complete reports (#2242)

Keep static feedback concise while retaining complete diagnostic reports,
visible lint errors, module-boundary checks, and the 3% duplication gate.
Upload complete reports after static failures and restore their outputs
from Turbo caches. Preserve unambiguous, checkout-relative clone locations.

Bind both lint caches to the website, documentation configuration and
experiment sources actually scanned by oxlint, including ignore policy.
Guard this ownership by comparing live checker discovery with resolved
Turbo inputs. A real website syntax error now invalidates a cached pass.

Validation: full current-head CI and the separate Go lane passed. Seven
real-checker regressions passed; failure-status and stale-report mutations
were rejected, and restored source passed. Actual Turbo restored both
reports byte-for-byte; full static/docs/workflow checks passed.

Closes #2238.
Refs #2190.

Assisted-by: Kogasa (gensokyo-skills:kogasa-surprise-testing)

.github/workflows/ci.yml

@@ -99,6 +99,15 @@ jobs:
         run: npm run test:python
       - if: needs.changes.outputs.code != 'true'
         run: npm run format:check
+      - name: Upload complete static diagnostics
+        if: always() && needs.changes.outputs.code == 'true'
+        uses: actions/upload-artifact@v4
+        with:
+          name: static-check-reports
+          path: .cache/static-checks/
+          include-hidden-files: true
+          if-no-files-found: ignore
+          retention-days: 7
 
   test-shard:
     name: Test shard (${{ matrix.shard }})