Phase 13.11.B: Taxonomy-based capability matrix (41 features)

Rewrote generate_capability_matrix.py v2: imports feature_taxonomy.py,
matches tests by pattern, uses @pytest.mark.invariance from keywords.
321 features → 41 curated features (PHASE_13_11_B approved, 3 reviewers).

1509 matched tests, 42 unmatched. 9 verified, 27 smoke-only, 4 broken
(pre-existing), 1 planned (SUB.clone).

Author: miranov25