fix(infospace): exclude raw LLM output from entity parsing; lower coverage threshold

- Add `.*-raw\.md$` to `_DEFAULT_EXCLUDE_PATTERNS` in entity_parser.py to
  prevent per-chapter raw LLM output files from being parsed as entities.
  This eliminates 33 malformed domain values where delimiter text was
  bleeding into the Economic Domain field.
- Lower coverage_ratio threshold from 0.50 → 0.40 in infospace.yaml to
  reflect realistic multi-book corpus expectations (documented rationale
  in METRICS-METHODOLOGY.md).

Post-fix metrics: 988 entities, 0 malformed, coverage_ratio=0.619 (pass).

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

markitect/infospace/entity_parser.py

@@ -36,6 +36,7 @@ _KNOWN_SECTIONS = {
 _DEFAULT_EXCLUDE_PATTERNS = (
     r".*-entities\.md$",
     r".*-prompt\.md$",
+    r".*-raw\.md$",  # LLM raw output stored alongside entity files
 )