feat(rulings): a command or edit touching an area's files shows its rulings, once per session (milestone 444 step 4, #4757)

A System's rulings (the Rulings section of its description) now reach the
work by path, not by similarity. Both PreToolUse arms resolve the files a
command or edit names to the Systems whose path_patterns cover them, and the
first touch in a session shows each area's rulings in one line; a repeat is
a one-line reference. A lookup, so no floor, no budget, no retrieval_logs row.

- services/system_rulings: parse_rulings, command_paths (reads and writes,
  relative to the repo root from any cwd; flags, URLs, globs skipped),
  rulings_for_paths
- /tool-rules takes root, cwd and seen_ruling_systems; /prior-art takes
  seen_ruling_systems; both return ruling_system_ids
- hooks share <sid>.rulings.ids (cleared on compaction by the ledger naming
  convention); the Bash hook sends the repo root and cwd
- system_usage_events (migration 0114): surfacings by source, pulls from
  get_system; carried by backup (v20) through the system map
- writing-records: rulings also arrive when the area's files are touched

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugin/hooks/scribe_defs.sh

@@ -1123,6 +1123,20 @@ scribe_held_query() {
   return 0
 }
 
+# The Systems whose rulings this session was already shown in full (milestone
+# 444), as the `seen_ruling_systems` query both PreToolUse hooks send. A flat
+# read, not aged like the rule file: a ruling binds for the whole session, and
+# the server already answers a repeat with one short reference line. The file
+# follows the ledger name convention, so a compaction clears it and the
+# rulings are shown in full again to the context that lost them.
+scribe_rulings_query() {
+  local ids
+  [ -f "$1" ] || return 0
+  ids=$(grep -E '^[0-9]+$' "$1" 2>/dev/null | sort -un | tr '\n' ',' | sed 's/,$//')
+  [ -n "$ids" ] && printf '&seen_ruling_systems=%s' "$ids"
+  return 0
+}
+
 # Drop EVERY per-session ledger, matched by convention rather than listed (#4101).
 #
 # A LIST IS THE BUG. Until now the compact/clear branch named its files one at