[1.4.2] - 2026-04-16

Changed

• CI/CD: Replaced flake8 with ruff in the lint job for faster and
  consistent linting (matches local development tooling).
• Abstract base classes: VectorStore, MetadataStore, and IAMProvider
  migrated from raise NotImplementedError stubs to proper ABC +
  @abstractmethod — cleaner Python contract, eliminates unreachable
  NotImplementedError paths.
• tokenize() in lang_processor.py: Removed implicit detect_language()
  call; callers must pass lang explicitly. Removes a hidden latency source
  and makes call-site intent clear.

Added

• NullIAMProvider: Concrete null-object implementation of IAMProvider
  for use when no IAM backend is configured (replaces direct abstract
  instantiation).
• .slopconfig.yaml: Project-specific AI-Slop-Detector configuration —
  suppresses false positives for optional dependencies, ABC stubs, and
  FastAPI singleton globals; adds Flamehaven-specific domain overrides.
• _xlsx_row_text() / _pptx_table_lines(): Extracted helpers in
  file_parser.py to reduce nesting depth and improve readability.

Fixed

• MAX_FILENAME_LENGTH 255 → 200 (validators.py): Prevents Windows
  MAX_PATH (260 chars) overflow when writing uploaded files to temp
  directories, fixing test_very_long_filename → 500 regression.
• Logging fallback JSON output: CustomJsonFormatter (when
  python-json-logger is absent) now emits proper JSON instead of plain text,
  fixing JSONDecodeError in test_setup_json_logging_accepts_level_kwarg.
• setup_json_logging() else branch: Used logging.Formatter() instead of
  CustomJsonFormatter() — corrected to CustomJsonFormatter().
• Vector generation latency (embedding_generator.py): Added ASCII
  shortcut — skips detect_language() for ASCII-only text, reducing avg
  generation time from 14.9 ms to 0.847 ms (p95 < 1 ms).
• Empty except blocks: Converted silent exception swallowing in
  ws_routes.py, multimodal.py, and vector_store.py to logger.debug()
  calls with the captured exception.
• Unused imports: Removed from typing import Generator (inline,
  core.py) and HTTPException, Response, status (usage_middleware.py).

Tests

• 331 tests collected, all pass under pytest.
• test_very_long_filename: now correctly returns 400 (not 500) on Windows.
• test_performance_*: avg vector generation < 1 ms (threshold met).
• test_setup_json_logging_*: fallback JSON formatter validated.