Fix lint debt and make CI gates honest

- ruff: fix all 328 errors (autofix + manual); move config to [tool.ruff.lint]
- mypy: fix all errors (annotations, nullable-column guards, stale kwargs
  in weekly report caller)
- black: reformat src/tests so black --check passes
- CI: remove `|| true` from ruff/black/mypy/pytest steps in both
  .gitea and .github workflows; install project deps and add mypy
  step in gitea python-ci so gates actually run
- docs: move 14 root status/guide markdown files into docs/, update links

.github/workflows/ci.yml

@@ -34,14 +34,15 @@ jobs:
           .venv/bin/pip install --upgrade pip
           .venv/bin/pip install -e ".[dev]"
 
+      # Linters are hard gates — no `|| true`.
       - name: Run linters
         run: |
           echo "Running ruff..."
-          .venv/bin/ruff check src/ tests/ || true
+          .venv/bin/ruff check src/ tests/
           echo "Running black check..."
-          .venv/bin/black --check src/ tests/ || true
+          .venv/bin/black --check src/ tests/
           echo "Running mypy..."
-          .venv/bin/mypy src/ --install-types --non-interactive || true
+          .venv/bin/mypy src/ --install-types --non-interactive
 
       - name: Run tests with coverage
         env: