feat(domain): rule groups — MP rule-string parser/serializer, builtin keywords, chain evaluation wired into slot

- rules/: RuleExpr tree, '>' layers with ! & | and parens, position-aware errors
  (unknown atom with suggestions, unsupported music atoms, parens, empty layer)
- builtin keyword table aligned with MP BUILTIN_RULE_SET; field-based judgement
  where parsed fields exist, MP regex otherwise; custom atoms (MP 7 fields)
- chain evaluation: hard excludes, ladder pri 100-k, groups AND-ed, pri from last
  laddered group, readable per-atom trace
- slot: SlotSpec.rules, rule.hard_exclude / rule.no_layer_matched violations,
  pri basis switches to priority when a rule ladder is present
- differential: 66 rule chains x 32 torrents vs MP python path (parse 64/64,
  pri 2090/2112, 22 registered mp_bug)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/domain/src/rules/index.ts

@@ -0,0 +1,32 @@
+export {
+  ATOM_ID_RE,
+  type AtomHit,
+  type AtomInput,
+  BUILTIN_ATOM_MAP,
+  BUILTIN_ATOMS,
+  type BuiltinAtom,
+  compileMpPattern,
+  customAtomFromMp,
+  testCustomAtom,
+} from "./atoms.ts";
+export {
+  type AtomCatalog,
+  catalogOf,
+  evaluateRuleChain,
+  evaluateRuleGroup,
+  matchesExpr,
+  testAtom,
+} from "./evaluate.ts";
+export {
+  atomsOf,
+  fromMpParseList,
+  normalizeExpr,
+  parseExpr,
+  parseRuleString,
+  type RuleParseOptions,
+  type RuleParseResult,
+  serializeExpr,
+  serializeLayers,
+  suggestAtoms,
+} from "./expr.ts";
+export * from "./types.ts";