docs(dev-seed): canonical doc updates + refactor-log entry

- CLAUDE.md Key Conventions: 'App bootstrap' rule rewritten as 'Three
  binding modes per feature' — describes USE_DEV_SEED + NODE_ENV
  resolution order and the new ./di/bind-dev-seed export.
- AGENTS.md (root): exports list now mentions ./ui + ./di/bind-dev-seed;
  Per-feature public-API surface table gains a row; Apps section shows
  the bindAll() dispatcher with three-rule logic.
- docs/architecture/vertical-feature-spec.md §6: file shape now
  includes bind-dev-seed.ts, bind-dev-seed.test.ts, __seeds__/dev.ts;
  package.json exports list updated to include ./di/bind-dev-seed.
- docs/architecture/data-flow-explainer.html: anatomy tree gains
  __seeds__/ row; LAYERS.di description updated with new binders +
  cross-link to di-explainer.html; new LAYERS.seeds entry; public-
  surface card expanded to six subpaths.
- docs/superpowers/refactor-logs/2026-05-06-input-output-unification.md
  §7: new 'Post-Plan-9: dev-seed binders' entry summarizing the rollout
  (commits, per-feature additions, app wiring, tests, turbo, docs).
- bind-production.test.ts: dispatcher tests use vi.stubEnv (typesafe
  way to test process.env in TypeScript 5+ with @types/node read-only
  process.env types). 4 dispatcher tests + 2 bindAllProduction tests
  = 7 tests total.

AGENTS.md

@@ -55,7 +55,7 @@ No other cross-package boundary deviations are permitted.
 ### Four enforcement layers
 
 1. **`package.json` dependencies** — only allowed deps are declared; illegal imports fail at install time.
-2. **`exports` maps** — feature packages expose `.`, `./cms`, `./api`, `./di/bind-production` only; no deep source paths exist.
+2. **`exports` maps** — feature packages expose `.`, `./ui`, `./cms`, `./api`, `./di/bind-production`, `./di/bind-dev-seed` only; no deep source paths exist.
 3. **ESLint `eslint-plugin-boundaries`** (lint-time) — configured in `packages/core-eslint/`:
    - Enforces the five-tag rules at linting
    - Feature packages may import from `core` and tooling only.
@@ -282,7 +282,8 @@ Each feature package exposes exactly these subpath exports:
 | `./ui` | Query builders (`queryOptions`), UI components | App packages |
 | `./api` | tRPC router (`xRouter` + `XRouter` type) | `@repo/core-api` only |
 | `./cms` | Payload collections | `@repo/core-cms` only |
-| `./di/bind-production` | App boot side-effect | App packages only |
+| `./di/bind-production` | App boot side-effect — swaps mock for real Payload impl | App packages only |
+| `./di/bind-dev-seed` | App boot side-effect — swaps empty mock for populated mock | App packages, storybook |
 
 Apps import schemas/types from `@repo/<feature>` (root) and React Query builders from `@repo/<feature>/ui`. Deep source paths are not accessible — the `exports` map enforces this.
 
@@ -305,9 +306,13 @@ export class ArticlesRepository implements IArticlesRepository {
 
 Class names carry no `Payload` prefix — `ArticlesRepository`, `PagesRepository`, `HeaderRepository`, etc. The config comes from the app at boot time (see below).
 
-### Apps call `bindProduction*()` per feature at boot
+### Apps call `bindAll()` per feature at boot
 
-Each app (`web-next`, `web-tanstack`, `cms`) imports feature `bindProduction*` functions and calls them at startup to swap mock implementations for Payload-backed ones:
+Each app (`web-next`, `web-tanstack`, `cms`) imports both binders per feature and uses a small dispatcher (`bindAll()`) that picks based on environment:
+
+- `USE_DEV_SEED === "true"` → dev seed (explicit override; works in any `NODE_ENV`)
+- `NODE_ENV === "production"` → production (real Payload)
+- otherwise → dev seed (developer default; `pnpm dev` boots without Payload)
 
 ```typescript
 // apps/web-next/src/server/bind-production.ts
@@ -316,8 +321,19 @@ import { bindProductionAuth } from "@repo/auth/di/bind-production";
 import { bindProductionMarketingPages } from "@repo/marketing-pages/di/bind-production";
 import { bindProductionNavigation } from "@repo/navigation/di/bind-production";
 import { bindProductionMedia } from "@repo/media/di/bind-production";
+import { bindDevSeedBlog } from "@repo/blog/di/bind-dev-seed";
+import { bindDevSeedAuth } from "@repo/auth/di/bind-dev-seed";
+import { bindDevSeedMarketingPages } from "@repo/marketing-pages/di/bind-dev-seed";
+import { bindDevSeedNavigation } from "@repo/navigation/di/bind-dev-seed";
+import { bindDevSeedMedia } from "@repo/media/di/bind-dev-seed";
 import config from "@repo/core-cms";
 
+export async function bindAll(): Promise<void> {
+  if (process.env.USE_DEV_SEED === "true") return bindAllDevSeed();
+  if (process.env.NODE_ENV === "production") return bindAllProduction();
+  return bindAllDevSeed();
+}
+
 export async function bindAllProduction(): Promise<void> {
   const resolvedConfig = await config;
   bindProductionAuth(resolvedConfig);