feat(routes): FastAPI prefixes, ASP.NET endpoint groups, wrapped server actions on the Screens tab

- python.ts postExtract: APIRouter(prefix=) and literal include_router(prefix=) composed down the include tree (module import, alias, local); a computed prefix leaves that mount alone; full-stack-fastapi-template 23 routes named by path
- csharp.ts: handler-first MapPost(Handler[, "path"]) under the endpoint-group class, the app's $"/api/{groupName}" head read in postExtract, RoutePrefix honoured; detection covers Endpoints/ files; CleanArchitecture 10 routes
- tier-synthesizer: a type argument between a client call and its parentheses (useSWR<T>(…), ky.get<T>(…)); recorded callee without it
- screens.ts: a file-scope navigation attributed to the value spanning it; a value nothing calls attributed to the functions mentioning it in importing files (request-time source read, bounded); steps.ts lends navigates edges to a value root
- tests: servers fixture (FastAPI prefixed routers, ASP.NET endpoint group end to end), frameworks.test.ts (group form, RoutePrefix), cross-tier (generic useSWR)
- docs: CHANGELOG, plan, playbook rows

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

docs/design/dynamic-dispatch-coverage-playbook.md

@@ -280,6 +280,8 @@ Status legend: ✅ done+validated · 🔬 hole identified · ⬜ not started.
 | TypeScript/JS | Next.js (App Router + Pages Router) | page → `<Link>` / `router.push` / `redirect` → page; page load → data; client component → `'use server'` action → DB → `redirect`; `route.ts` handler → DB → response | R + S | ✅ 2026-08-28 (`frameworks/nextjs.ts`, `next-router-synthesizer.ts`, Steps `load` trigger + server-action crossing): fixture `__tests__/nextjs.test.ts` end to end (Screens `routed`, the push attributed back under its condition, the action's redirect); `leerob/next-saas-starter` indexes its pages and links. 🔬 agent A/B (`--model sonnet`, ≥2 runs/arm) not run yet |
 | TypeScript/JS | Express + React (MERN monorepo) | client `axios` / `fetch` literal path → own route → handler → Mongoose → response rows | S + R | ✅ 2026-08-28 (`tier-synthesizer.ts` `http-client` + Express mounts / chained `router.route()` / wrapped `const h = asyncHandler(…)` handlers / nested `package.json` detection): `bradtraversy/proshop_mern` 49 routes (19 pages + 30 endpoints), 23 client→route edges, every one spot-checked correct; `login → ⇢ POST /api/users/login → User.findOne → 401 rows → jwt.sign`. Node count stable across re-index. 🔬 A/B not run |
 | TypeScript/JS | NestJS queues / events / sockets | `queue.add('job')` → `@Process('job')`; `emit('x')` → `@OnEvent('x')`; `socket.emit` → `@SubscribeMessage` and `server.emit` → `socket.on` | S | ✅ 2026-08-28 (`tier-synthesizer.ts` `queue-job`, `event-bus`): `nestjs/nest` `sample/26-queues` (`transcode` → `handleTranscode`) and `sample/30-event-emitter` (`order.created` → its listener) exact, 0 wrong edges after the `e2e/` and generic-event guards; `immich-app/immich` 0 edges — a generated SDK client and a wrapped queue API carry no literal, so silence (correct). 🔬 A/B not run |
+| Python | FastAPI (prefixed routers) | request → `Depends` → handler → session → `HTTPException` rows | R | ✅ 2026-08-28 `python.ts` `postExtract` composes `APIRouter(prefix=)` + literal `include_router(prefix=)`: `fastapi/full-stack-fastapi-template` 23 routes named `GET /items/{id}`, `POST /login/access-token` (were `GET /`); a computed mount prefix is skipped. 🔬 A/B not run |
+| C# | ASP.NET Minimal API endpoint groups | request → group handler → `ISender.Send` → `TypedResults` rows | R | ✅ 2026-08-28 `csharp.ts` handler-first `MapPost(Handler[, path])` under the class + `$"/api/{groupName}"` head (`jasontaylordev/CleanArchitecture` shape); fixture end to end in `ui-steps-api-servers.test.ts` (`PUT /api/TodoItems/{id}` → `204 · 400` rows); `jasontaylordev/CleanArchitecture` 10 routes, all the app's endpoints (were 0). 🔬 A/B not run |
 
 ### Retrieval A/Bs that are not coverage work