session-memory: map signals to catalog recommendations via covers (WP-0010 follow-up)

Closes the gap where recurring_error suggestions showed generic 'Investigate'
instead of the curated recommendation. Added a covers[] field to SolutionPattern
(lowercase substrings a pattern's recommendation also applies to) + Catalog.find_for
(exact key first, then covers match against signal key+locus). Retro now resolves
recommendations through find_for. Tagged the read-before-edit pattern with
covers=['file has not been read','modified since read','file_not_read'] (v1.0.1).
Live: file-not-read suggestions across all repos now inherit 'Read the file before
Edit/Write'. 6 new tests; suite 158/158.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

session_memory/curate/schema.py

@@ -81,6 +81,11 @@ class SolutionPattern:
     # per-flavor rendering hints, kept OUT of the agnostic core (OQ4):
     #   {"claude": {...}, "codex": {...}, "grok": {...}}
     rendering_hints: dict[str, dict[str, Any]] = field(default_factory=dict)
+    # other signal keys/loci this pattern's recommendation also applies to —
+    # lowercase substrings matched against a candidate signal's key+locus, so a
+    # detect signal that doesn't share this pattern's exact key (e.g. a
+    # recurring_error fingerprint) can still inherit the curated resolution.
+    covers: list[str] = field(default_factory=list)
     status: str = "provisional"
     distribution_ready: bool = False
     created_at: Optional[str] = None