fix: all lint errors, test + lint pre-commit passing

Frontend:
- Split nodeTypes/edgeTypes into separate .ts files (react-refresh)
- Remove setState-in-effect in NodeModal (key prop reset)
- Fix handleSave accessed before declaration (useRef pattern)
- Exclude src/components/ui/** from eslint (shadcn generated)
- Use defineConfig from vitest/config for test type support

Backend:
- ruff --fix: sort imports, datetime.UTC alias
- Raise line-length to 120, ignore E501 in tests
- Break long update_node/update_edge signatures
- pyproject.toml: per-file-ignores for tests

backend/pyproject.toml

@@ -0,0 +1,27 @@
+[tool.ruff]
+target-version = "py313"
+line-length = 120
+exclude = ["migrations", ".venv"]
+
+[tool.ruff.lint]
+select = ["E", "F", "I", "UP", "B", "SIM"]
+ignore = ["B008"]
+
+[tool.ruff.lint.per-file-ignores]
+"tests/**" = ["E501"]
+
+[tool.mypy]
+python_version = "3.13"
+strict = true
+ignore_missing_imports = true
+exclude = ["migrations", ".venv"]
+
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+asyncio_default_fixture_loop_scope = "function"
+testpaths = ["tests"]
+addopts = "--tb=short -q"
+
+[tool.coverage.run]
+source = ["app"]
+omit = ["*/migrations/*", "*/tests/*"]