X/Twitter structural support + per-package tsconfig scoping

X/Twitter (live posting gated on an X developer app, registered separately):
- schema: add 'twitter' to OutletSchema (sanitize 280-char limit already present).
- packages/twitter-client: X API v2 client (POST /2/tweets, OAuth2 user Bearer),
  injectable fetch, 280-char guard; 4 contract tests.
- apps/scheduler/src/dispatch.ts: makeOutletDispatcher routes by outlet
  (linkedin.* -> linkedin, twitter -> twitter), fail-closed for unconfigured
  outlets; 4 tests. main.ts wires both outlets fail-closed until creds exist.

Monorepo fix: add a local tsconfig.json (extends root, include src) to each
package + non-admin app. Without it, every package's `tsc --noEmit` compiled the
WHOLE repo via the root config (no JSX/DOM) and choked on the admin .tsx — masked
until now by turbo build caching.

Tests: 135 passing + 13 gated across 12 tasks.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/twitter-client/package.json

@@ -0,0 +1,21 @@
+{
+  "name": "@stargue/twitter-client",
+  "version": "0.1.0",
+  "private": true,
+  "type": "module",
+  "main": "./src/index.ts",
+  "types": "./src/index.ts",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "build": "tsc --noEmit",
+    "typecheck": "tsc --noEmit",
+    "test": "vitest run",
+    "lint": "echo 'lint pending'"
+  },
+  "devDependencies": {
+    "vitest": "^2.1.0",
+    "typescript": "^5.7.0"
+  }
+}