governance + docs quick-wins batch (T-113)

- Amend D-66: floor lives at coverage_floor: in pubspec.yaml (single
  source of truth); coverage/floor.txt is no longer used; 95% target
  reached and is the current floor.
- Reconcile licenses.yaml with pubspec.yaml: drop the phantom lints
  5.0.0 entry (not a direct dep), bump test to 1.30.0 to match
  pubspec, tighten the purpose line.
- Triage Q-1/Q-2/Q-3/Q-25 with dated revisit notes: all still open,
  each pending a concrete trigger (T-99 for Q-1/Q-2, Tier-6 audit
  for Q-3, design call for Q-25).
- Drop --no-fatal-infos from ci/test.sh now that the import queue is
  clean.
- Add .claude/skills/README.md inventory.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

assets/licenses.yaml

@@ -216,21 +216,11 @@ dev_dependencies:
     license: BSD-3-Clause
     purpose: Flutter-team-recommended analyzer lint set (app/).
 
-  - name: lints
-    kind: dart-package
-    version: "5.0.0"
-    homepage: https://pub.dev/packages/lints
-    license: BSD-3-Clause
-    purpose: >-
-      Dart-team-recommended analyzer lint set for the Flutter-free
-      core package at the repo root.
-
   - name: test
     kind: dart-package
-    version: "1.25.8"
+    version: "1.30.0"
     homepage: https://pub.dev/packages/test
     license: BSD-3-Clause
     purpose: >-
-      Dart test runner for the core package (Flutter-free; the app
-      uses flutter_test from the Flutter SDK for widget + golden
-      coverage).
+      Dart test runner for the Flutter-free PTY tests under
+      `dart test --tags forkpty` (flutter_test is used elsewhere).