feat(turbo): turbo gen feature generator (Phase 1, single-entity)

Adds `pnpm turbo gen feature` to scaffold a Lazar-conformant feature
package matching the navigation reference shape: entity + Zod schema,
single use case (`get<Entity>`), controller, mock + Payload-stub real
repository (with span + capture), DI module/container/symbols, and tRPC
router with full BAD_REQUEST/NOT_FOUND error mapping. The generated
`bind-production.ts` and `bind-dev-seed.ts` compose the post-R44
`withSpan(tracer, opts, withCapture(logger, tags, factory(deps)))`
sandwich at bind time.

Verified by generating a sample `packages/example/` feature and running
`pnpm --filter @repo/example lint typecheck test` — all three pass
(9 test files, 25 tests). Cleaned up after verification so no example
package is committed.

Phase-1 limitations (documented in `docs/guides/scaffolding-a-feature.md`
and printed by the generator on success): no Payload CMS templates, no
React Query helpers, faker-driven factories left as stubs, single
entity / single use case, and aggregator wiring (core-api/root,
apps/web-next bindAll) is left as a manual checklist.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

turbo/generators/templates/feature/src/interface-adapters/controllers/get-entity.controller.ts.hbs

@@ -0,0 +1,23 @@
+import { InputParseError } from "../../entities/errors/common";
+import {
+  get{{pascalCase entity}}InputSchema,
+  type Get{{pascalCase entity}}Output,
+  type IGet{{pascalCase entity}}UseCase,
+} from "../../application/use-cases/get-{{kebabCase entity}}.use-case";
+
+function presenter(value: Get{{pascalCase entity}}Output) {
+  return value;
+}
+
+export type IGet{{pascalCase entity}}Controller = ReturnType<typeof get{{pascalCase entity}}Controller>;
+
+export const get{{pascalCase entity}}Controller =
+  (get{{pascalCase entity}}UseCase: IGet{{pascalCase entity}}UseCase) =>
+  async (input: unknown): Promise<ReturnType<typeof presenter>> => {
+    const parsed = get{{pascalCase entity}}InputSchema.safeParse(input);
+    if (!parsed.success) {
+      throw new InputParseError("Invalid get-{{kebabCase entity}} input", { cause: parsed.error });
+    }
+    const result = await get{{pascalCase entity}}UseCase(parsed.data);
+    return presenter(result);
+  };