feat(screens): Next.js as a Screens app — pages, route handlers, links and redirects

- frameworks/nextjs.ts (split out of react.ts): App Router app/**/page.tsx and Pages Router pages → routes named by path ((group) stripped, [slug] → :slug, [...all] → :all*), bound to the default export; app/**/route.ts exports → METHOD /api/… endpoints referencing their functions; pages/api → ANY; resolve() claims router.push/replace/prefetch, redirect/permanentRedirect and NextResponse.redirect(new URL(…)) into navigates edges via the Expo href readers, against a Next-only route table gated on the app's root
- next-router-synthesizer.ts: <Link href> and internal <a href> → dashed navigates edges from the component (next-link, registeredAt)
- expo-router.ts: href readers exported; matcher accepts :param / :all* segments
- steps.ts: a Next page's own work fires from page load; a Next page makes the project a web app; {status: 201} read off the call site (branch-guards CallSiteText.status) for response rows
- frameworks/package-deps.ts: nested package.json files probed on disk (getAllFiles lists only sources); Express/React/Expo/Nest detectors use it; routing manifest names constant handlers
- tests: nextjs.test.ts (file→route rules, extract, verbs, end to end with Screens and Steps); frameworks.test.ts Next cases moved to the Next resolver
- docs: CHANGELOG, spec §3.12 frameworks paragraph, CLAUDE.md, synthesis doc, plan P4 built, playbook rows for Next / MERN / Nest channels

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01REFyW9hmNrxhwN5wxRoAkC

CLAUDE.md

@@ -76,7 +76,7 @@ The public API surface is `src/index.ts` — the `CodeGraph` class wires all the
 - `src/index.ts` — `CodeGraph` class: `init`/`open`/`close`, `indexAll`, `sync`, `searchNodes`, `getCallers`/`getCallees`, `getImpactRadius`, `buildContext`, `watch`/`unwatch`.
 - `src/db/` — `DatabaseConnection`, `QueryBuilder` (prepared statements), `schema.sql`, `sqlite-adapter.ts`. Backed by Node's built-in **`node:sqlite`** (`DatabaseSync`) — real SQLite with WAL + FTS5, exposed through a thin better-sqlite3-shaped adapter. The bundled runtime always ships Node ≥22.5, so `node:sqlite` is always available: **no native build step and no wasm fallback**. (Running from source needs Node ≥22.5.) `codegraph status` reports the live backend (`node-sqlite`, the sole backend).
 - `src/extraction/` — `ExtractionOrchestrator`, tree-sitter wrappers, per-language extractors under `languages/` (one file per language), plus standalone extractors for non-tree-sitter formats (`svelte-extractor.ts`, `vue-extractor.ts`, `liquid-extractor.ts`, `dfm-extractor.ts` for Delphi). `parse-worker.ts` runs heavy parsing off the main thread.
-- `src/resolution/` — `ReferenceResolver` orchestrates `import-resolver.ts` (with `path-aliases.ts` for tsconfig path aliases + cargo workspace member globs), `name-matcher.ts`, and `frameworks/` (Express, Laravel, Rails, FastAPI, Django, Flask, Spring, Gin, Axum, ASP.NET, Vapor, React Router, SvelteKit, Vue/Nuxt, Cargo workspaces). Frameworks emit `route` nodes and `references` edges. `callback-synthesizer.ts` holds the whole-graph synthesis passes (`SYNTH_PASSES`, merged in registry order — first-seen wins a duplicate pair) with the language gates; `tier-synthesizer.ts` is the cross-tier pass (a client's literal `fetch`/`axios` path onto its own route, a queue job onto its consumer, a bus / socket event onto its handler — `channel`, `tier`, `registeredAt` on every edge; registered before the in-process emitter pass so its more specific edge wins); `synth-utils.ts` has the helpers they share (`enclosingFn`, `enclosingValue`, `makeLineAt`). Express's `postExtract` composes `app.use('/prefix', router)` mounts onto a mounted file's route names, idempotently (the original path stays in `qualifiedName`).
+- `src/resolution/` — `ReferenceResolver` orchestrates `import-resolver.ts` (with `path-aliases.ts` for tsconfig path aliases + cargo workspace member globs), `name-matcher.ts`, and `frameworks/` (Express, Laravel, Rails, FastAPI, Django, Flask, Spring, Gin, Axum, ASP.NET, Vapor, React Router, Next.js — `nextjs.ts`: pages and `route.ts` handlers from files, `router.push` / `redirect` / `NextResponse.redirect` as `navigates` edges, with `next-router-synthesizer.ts` for `<Link href>` — Expo Router, SvelteKit, Vue/Nuxt, Cargo workspaces). Frameworks emit `route` nodes and `references` edges. `callback-synthesizer.ts` holds the whole-graph synthesis passes (`SYNTH_PASSES`, merged in registry order — first-seen wins a duplicate pair) with the language gates; `tier-synthesizer.ts` is the cross-tier pass (a client's literal `fetch`/`axios` path onto its own route, a queue job onto its consumer, a bus / socket event onto its handler — `channel`, `tier`, `registeredAt` on every edge; registered before the in-process emitter pass so its more specific edge wins); `synth-utils.ts` has the helpers they share (`enclosingFn`, `enclosingValue`, `makeLineAt`). Express's `postExtract` composes `app.use('/prefix', router)` mounts onto a mounted file's route names, idempotently (the original path stays in `qualifiedName`).
 - `src/graph/` — `GraphTraverser` (BFS/DFS, impact radius, path finding) and `GraphQueryManager` (high-level queries), plus the shared query-time derivations more than one surface renders: `named-symbol-flow.ts` (the one path finder, behind `codegraph_explore`'s Flow section and the viewer's Flow strip), `dynamic-boundary-report.ts` (where the graph stops), `type-hierarchy.ts` (ancestors/subtypes and the implementation count explore prints and the viewer draws),
   `dead-code.ts` (unreferenced symbols, and every reason a candidate is NOT claimed). A derivation that two callers render must live here, not in `ToolHandler` — two derivations eventually disagree.
 - `src/context/` — `ContextBuilder` + formatter for markdown/JSON output.