refactor: restructure project layout and add install.mjs

- Move src/ → plugin/ with subdirectories:
  - plugin/core/ (business logic, models, store, permissions, utils, memory)
  - plugin/tools/ (query, resources)
  - plugin/commands/ (placeholder for slash commands)
  - plugin/hooks/ (placeholder for lifecycle hooks)
  - plugin/index.ts (wiring layer only, no business logic)
- Add install.mjs with --install, --uninstall, --openclaw-profile-path
- Add skills/ and docs/ root directories
- Move planning docs (PLAN.md, FEAT.md, AGENT_TASKS.md) to docs/
- Remove old scripts/install.sh
- Update tsconfig rootDir: src → plugin
- Update README.md and README.zh.md with new layout
- Bump version to 0.2.0
- All tests pass

plugin/tools/query.ts

@@ -0,0 +1,75 @@
+import { YonexusError } from '../core/models/errors';
+import type { Identity, QueryFilter, QueryInput, QueryOptions, YonexusSchema } from "../core/models/types";
+
+const DEFAULT_LIMIT = 20;
+const MAX_LIMIT = 100;
+
+const regexCache = new Map<string, RegExp>();
+const containsCache = new Map<string, string>();
+
+function getRegex(pattern: string): RegExp {
+  const cached = regexCache.get(pattern);
+  if (cached) return cached;
+  const created = new RegExp(pattern);
+  regexCache.set(pattern, created);
+  return created;
+}
+
+function normalizeNeedle(value: string): string {
+  const cached = containsCache.get(value);
+  if (cached) return cached;
+  const normalized = value.toLowerCase();
+  containsCache.set(value, normalized);
+  return normalized;
+}
+
+function isQueryable(field: string, schema: YonexusSchema): boolean {
+  return Boolean(schema[field]?.queryable);
+}
+
+function matchFilter(identity: Identity, filter: QueryFilter): boolean {
+  const raw = identity.meta[filter.field] ?? "";
+
+  switch (filter.op) {
+    case "eq":
+      return raw === filter.value;
+    case "contains":
+      return raw.toLowerCase().includes(normalizeNeedle(filter.value));
+    case "regex": {
+      const re = getRegex(filter.value);
+      return re.test(raw);
+    }
+    default:
+      return false;
+  }
+}
+
+function normalizeOptions(options?: QueryOptions): Required<QueryOptions> {
+  const limit = Math.min(Math.max(1, options?.limit ?? DEFAULT_LIMIT), MAX_LIMIT);
+  const offset = Math.max(0, options?.offset ?? 0);
+  return { limit, offset };
+}
+
+function sortFilters(filters: QueryFilter[]): QueryFilter[] {
+  const weight = (f: QueryFilter): number => {
+    if (f.op === 'eq') return 1;
+    if (f.op === 'contains') return 2;
+    return 3;
+  };
+  return [...filters].sort((a, b) => weight(a) - weight(b));
+}
+
+export function queryIdentities(identities: Identity[], input: QueryInput, schema: YonexusSchema): Identity[] {
+  for (const filter of input.filters) {
+    if (!isQueryable(filter.field, schema)) {
+      throw new YonexusError('FIELD_NOT_QUERYABLE', `field_not_queryable: ${filter.field}`, {
+        field: filter.field
+      });
+    }
+  }
+
+  const orderedFilters = sortFilters(input.filters);
+  const filtered = identities.filter((identity) => orderedFilters.every((f) => matchFilter(identity, f)));
+  const { limit, offset } = normalizeOptions(input.options);
+  return filtered.slice(offset, offset + limit);
+}