feat(extraction): index Vuex/Pinia store actions, mutations, and getters

A Vue store's callable surface — Vuex `actions`/`mutations`/`getters` and Pinia
store actions — lived only as object-literal properties, so the symbols an agent
looks for (`login`, `getSessionList`, `getAuthMenuList`) were never nodes:
`codegraph search`/`codegraph_node` returned "not found" and the agent had to
read the store by hand. This extracts them as function nodes (with their real
bodies + callees), the foundation under any later dispatch-bridge synthesis.

A corpus probe (vue-element-admin, vue2-elm, Geeker-Admin, MallChatWeb) showed
Vue store dispatch is NOT one clean string-keyed shape but ~5; extraction here
covers the three dominant definition forms:
  - Vuex MODULE: non-exported `const actions/mutations = {…}` collections
    (gated by a ≥2-signal looksLikeVueStoreFile + the object-of-functions shape,
    so a Redux file's stray `const actions` is a 0-node no-op).
  - Pinia OPTIONS: `defineStore({ actions: {…}, getters: {…} })` — methods of
    the actions/mutations/getters properties of a store-factory config.
  - Pinia SETUP: `defineStore('id', () => { const foo = …; return {…} })` — the
    body-local function consts (findPiniaSetupFn + extractPiniaSetupBody; the
    generic body walk doesn't reach nested function scopes). Distinguished from
    an inline action map via objectHasInlineFunctions so zustand/SvelteKit
    extraction is unchanged.

Validated findable on element-admin (50 fns), Geeker (21), MallChat (68);
0-node no-op on a non-Vue control (uwave-web, unchanged at 4496 nodes). Deferred
(documented in the backlog): vue2-elm's `export default {…}` split-file +
computed-key `commit(CONST)` form (n=1), and the dispatch BRIDGE synthesis
(Vuex string-key + Pinia useStore().action()). Suite green (1610); new
__tests__/vue-store-extraction.test.ts.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -11,6 +11,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### New Features
 
+- Vue store actions, mutations, and getters are now indexed as symbols you can find and read. Whether your store is **Vuex** (`mutations` / `actions` objects in a module) or **Pinia** — both the options form (`defineStore({ actions: { … } })`) and the setup form (`defineStore('id', () => { … })`, where actions are local functions) — each action, mutation, and getter is now a real node. So `codegraph search` finds `login` or `getSessionList`, and `codegraph_explore` / `codegraph_node` show its body and what it calls, instead of "not found" because the function only existed as an object-literal property. (Connecting a component's `dispatch('user/login')` / `store.action()` call through to the action is a separate follow-up.)
 - `codegraph_explore` now connects React data-fetching flows built on **RTK Query** (Redux Toolkit's `createApi`). An endpoint defined inside `createApi({ endpoints })` and the `useGetXQuery` / `useUpdateYMutation` hook it generates were both invisible to analysis — so "what does this component fetch?" or "where does `useGetThingQuery` get its data?" dead-ended, because the hook, the endpoint, and the component had nothing linking them. CodeGraph now indexes each endpoint and each generated hook as real symbols and wires the path `component → useGetXQuery → getX → queryFn`, so the flow resolves in one explore call instead of reading the API slice by hand. Both the arrow (`endpoints: build => ({ … })`) and method (`endpoints(builder) { return { … } }`) styles are recognized, along with the `useLazyGetXQuery` variant; hand-written hooks of a similar name are left untouched.
 
 - `codegraph_explore` now surfaces the right code in large multi-layer projects. When you ask a backend-flow question in a repo that pairs an API server with a big frontend that mirrors the same domain words — say an `app/` admin UI sitting over an `api/` server — the server-side file that genuinely matches several of your query's terms is no longer pushed out of the results by the larger, more interconnected frontend layer. A file corroborated by two or more distinct query terms is now kept in the answer even when a denser unrelated layer would otherwise crowd it out, so "how does X read items / handle the request" returns the service or handler that does the work instead of a wall of frontend views. Single-layer projects are unaffected; set `CODEGRAPH_RANK_NO_MULTITERM=1` to revert to the previous ranking.