fix(ci): use uv run instead of .venv/bin paths in CI workflow

The Gitea Actions runner containers don't expose .venv/bin on the
expected path. Using uv run lets uv resolve the correct environment.

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

.gitea/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
         run: uv sync --frozen
 
       - name: Run ruff
-        run: .venv/bin/ruff check .
+        run: uv run ruff check .
 
   # ---------------------------------------------------------------------------
   # Tests
@@ -84,7 +84,7 @@ jobs:
         run: uv sync --frozen
 
       - name: Run tests
-        run: .venv/bin/python -m pytest tests/ -v --tb=short
+        run: uv run python -m pytest tests/ -v --tb=short
 
   architecture:
     runs-on: ubuntu-latest
@@ -105,7 +105,7 @@ jobs:
         run: uv sync --frozen
 
       - name: Validate architecture
-        run: .venv/bin/python scripts/validate/validate_architecture.py
+        run: uv run python scripts/validate/validate_architecture.py
 
   # ---------------------------------------------------------------------------
   # Security (non-blocking)
@@ -143,7 +143,7 @@ jobs:
         run: uv sync --frozen
 
       - name: Run audit
-        run: .venv/bin/python scripts/validate/validate_audit.py
+        run: uv run python scripts/validate/validate_audit.py
 
   # ---------------------------------------------------------------------------
   # Build (docs - only on push to master)
@@ -166,7 +166,7 @@ jobs:
         run: uv sync --frozen
 
       - name: Build docs
-        run: .venv/bin/mkdocs build
+        run: uv run mkdocs build
 
       - name: Upload docs artifact
         uses: actions/upload-artifact@v4