chore: consolidate to single ruff config in root pyproject.toml

- Merge web ruff settings (select E/F/I/UP, line-length 100) into root config
- Remove [tool.ruff] section from web/pyproject.toml
- Remove "web" from root ruff exclude list
- Simplify pre-commit hook to one command: ruff check .
- Update CI to use: uv run ruff check . (from repo root)

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

pyproject.toml

@@ -88,14 +88,15 @@ exclude = [
     "site-packages",
     "venv",
     "notebooks",
-    "web",
 ]
 
+line-length = 100
 indent-width = 4
 
 target-version = "py313"
 
 [tool.ruff.lint]
+select = ["E", "F", "I", "UP"]
 
 ignore = [
     "E501",    # line too long (handled by formatter)