feat: task 1.3 vite dev proxy + tsconfig hardening

Same-origin dev proxy via Vite's server.proxy:
- /api/*       -> ${VITE_DEV_DIRECTUS_URL}/*   (Directus REST + GraphQL)
- /ws-business -> ws://.../websocket           (Directus business-plane WS)
- /ws-live     -> ${VITE_DEV_PROCESSOR_WS_URL} (Processor live WS, Phase 1.5)

WS proxy targets derive ws:// scheme from the http(s) Directus URL.
loadEnv reads VITE_DEV_* overrides; sensible localhost defaults.

tsconfig.app.json: noUncheckedIndexedAccess + noImplicitOverride.

.env.example documents the two override vars; .env.local is gitignored
via the existing *.local pattern.

README "Local dev" section: proxy table + override instructions + port
collision workaround.

Deviation: spec called for .env.dev.example/.env.dev.local but Vite's
dev mode is "development" not "dev", so mode-specific files would be
.env.development.* and Vite wouldn't auto-load .env.dev.local. Switched
to the standard Vite .env.example/.env.local convention. Documented in
the task's Done section.

Plus: backfill 1.2 commit SHA (9918418) in its Done section.

.planning/ROADMAP.md

@@ -50,8 +50,8 @@ These rules govern every task. Any deviation must be discussed and documented as
 | #    | Task                                                                                                         | Status | Landed in |
 | ---- | ------------------------------------------------------------------------------------------------------------ | ------ | --------- |
 | 1.1  | Project scaffold (Vite + React + TS)                                                                         | 🟩     | (manual)  |
-| 1.2  | [Stack rounding-out (Tailwind + shadcn/ui + deps + Prettier)](./phase-1-foundation/02-stack-rounding-out.md) | 🟩     | local (uncommitted) |
-| 1.3  | [Vite dev proxy + path aliases + tsconfig hardening](./phase-1-foundation/03-vite-dev-proxy.md)              | ⬜     | —         |
+| 1.2  | [Stack rounding-out (Tailwind + shadcn/ui + deps + Prettier)](./phase-1-foundation/02-stack-rounding-out.md) | 🟩     | `9918418` |
+| 1.3  | [Vite dev proxy + path aliases + tsconfig hardening](./phase-1-foundation/03-vite-dev-proxy.md)              | 🟩     | `PENDING_SHA` |
 | 1.4  | [Runtime config endpoint](./phase-1-foundation/04-runtime-config.md)                                         | ⬜     | —         |
 | 1.5  | [Directus auth client (cookie mode + refresh)](./phase-1-foundation/05-directus-auth-client.md)              | ⬜     | —         |
 | 1.6  | [Login page](./phase-1-foundation/06-login-page.md)                                                          | ⬜     | —         |