feat(systems): the area vocabulary becomes a global table so a rule can point at one (#3027, milestone 307 step 1)

The eight standard area names already existed — as STANDARD_SYSTEMS, a tuple in
services/systems.py that milestone 297 seeds at inception. A constant cannot be
a foreign key, so nothing outside a project could reference an area: systems.
project_id is NOT NULL, and a rule that spans projects would have to chain
itself to one project's row. And because the list only ever applied on the
inception-seed path, three spellings of one area reached this instance anyway
(CI & runners / CI and Release / CI & release).

- canonical_systems: global, no user_id — a shared project inherits the
  vocabulary instead of re-earning it. Migration 0087 seeds the same eight.
- systems.canonical_id: nullable, SET NULL. Association only — no System is
  renamed and record_systems is untouched, so no record's tags move.
- canonical_slug folds &/and, case and punctuation, so spelling variants map
  mechanically and a real difference ("CI & runners") becomes a proposal a
  human confirms. propose_mappings reports; set_system_canonical is the only
  writer.
- seed_standard_systems now reads the catalog and maps as it mints, so a
  project born standard never needs a reconciliation pass.
- Catalog writes are admin-only; reads are open — a global list anyone can
  extend stops being shared.
- backup: carried by SLUG, not id (ids are per-install). Restore reuses the
  target's own rows and only creates entries an admin added on the source; an
  unknown slug restores unmapped rather than failing.

Rule 22: STANDARD_SYSTEMS is removed, not deprecated. Rule 115: nothing seeded
names an app, repo or house convention. Design in note 3026.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

tests/test_integration_inception.py

@@ -13,6 +13,7 @@ from scribe.models.project import Project
 from scribe.models.rulebook import Rulebook
 from scribe.services import inception as inception_svc
 from scribe.services import rulebooks as rulebooks_svc
+from scribe.services import canonical_systems as canonical_svc
 from scribe.services import systems as systems_svc
 from tests.helpers import ensure_user
 
@@ -62,7 +63,11 @@ async def test_decide_applies_every_effect_and_records_last(seeded):
     })
     assert out["effects"]["excluded"] == [seeded["always"]]
     assert out["effects"]["subscribed"] == [seeded["other"]]
-    assert len(out["effects"]["systems_seeded"]) == len(systems_svc.STANDARD_SYSTEMS)
+    catalog = await canonical_svc.list_canonical_systems()
+    assert len(out["effects"]["systems_seeded"]) == len(catalog)
+    # Seeded Systems come out mapped, not needing a later reconciliation.
+    seeded_systems = await systems_svc.list_systems(owner, pid)
+    assert all(s.canonical_id is not None for s in seeded_systems)
 
     # The exclusion is total: the project's always-on set is empty, the
     # departure is named, the subscription binds.
@@ -81,7 +86,7 @@ async def test_decide_applies_every_effect_and_records_last(seeded):
     # Re-deciding with seed again mints nothing twice; include reverses the exclusion.
     again = await inception_svc.decide(owner, pid, via="ui", choices={"seed_systems": True})
     assert again["effects"]["systems_seeded"] == []
-    assert len(await systems_svc.list_systems(owner, pid)) == len(systems_svc.STANDARD_SYSTEMS)
+    assert len(await systems_svc.list_systems(owner, pid)) == len(catalog)
     await rulebooks_svc.include_always_on_rulebook_for_project(pid, seeded["always"], owner)
     assert [r.title for r in await rulebooks_svc.list_always_on_rules(owner, project_id=pid)] == ["dev is home"]