Round 2 review follow-ups:
- Add Field(max_length=20) to the nc_semantic_search path_prefixes param so
an LLM client can't build an unbounded OR-filter (mirrors the cap the
Astrolabe PHP controller applies on the UI path).
- Note in normalize_path_prefixes that the two-pass collect-then-strip is
deliberate (the `if path_prefix:` guard is truthy for whitespace-only
input; the strip pass is what drops it).
- Tests: exercise build_base_filter_conditions with 3 folders (guards the
list comprehension) and parametrize the no-path case over None, empty
list, and blank-only inputs.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>