Merge Luma launcher fork into monorepo

Move trampoline files (boot-hook, watcher, overlay) into trampoline/
subdirectory. Add upstream Luma v2.3.1 source at repo root with our
additions:

- Page::Ha (4th nav tab) with placeholder empty state
- HA tab config schema and default entity mapping (ha-home/)
- Nav keys renamed: "home" → "start", new "ha" tab between Apps and Settings
- All state.rs/view.rs/main.rs/tests.rs updated for 4-tab navigation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.oxfmtrc.json

@@ -0,0 +1,18 @@
+{
+  "$schema": "./node_modules/oxfmt/configuration_schema.json",
+  "singleQuote": true,
+  "printWidth": 100,
+  "trailingComma": "all",
+  "sortPackageJson": false,
+  "overrides": [{ "files": ["tv/*.cjs"], "options": { "trailingComma": "none" } }],
+  "ignorePatterns": [
+    "node_modules/**",
+    "dist/**",
+    ".build/**",
+    "target/**",
+    "pnpm-lock.yaml",
+    "assets/fonts/**",
+    "assets/licenses/**",
+    "assets/ui-icons/**"
+  ]
+}