move pi-mono into companion-cloud as apps/companion-os

- Copy all pi-mono source into apps/companion-os/
- Update Dockerfile to COPY pre-built binary instead of downloading from GitHub Releases
- Update deploy-staging.yml to build pi from source (bun compile) before Docker build
- Add apps/companion-os/** to path triggers
- No more cross-repo dispatch needed

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

biome.json

@@ -0,0 +1,39 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.3.5/schema.json",
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true,
+      "style": {
+        "noNonNullAssertion": "off",
+        "useConst": "error",
+        "useNodejsImportProtocol": "off"
+      },
+      "suspicious": {
+        "noExplicitAny": "off",
+        "noControlCharactersInRegex": "off",
+        "noEmptyInterface": "off"
+      }
+    }
+  },
+  "formatter": {
+    "enabled": true,
+    "formatWithErrors": false,
+    "indentStyle": "tab",
+    "indentWidth": 3,
+    "lineWidth": 120
+  },
+  "files": {
+    "includes": [
+      "packages/*/src/**/*.ts",
+      "packages/*/test/**/*.ts",
+      "packages/web-ui/src/**/*.ts",
+      "packages/web-ui/example/**/*.ts",
+      "!**/node_modules/**/*",
+      "!**/test-sessions.ts",
+      "!**/models.generated.ts",
+      "!packages/web-ui/src/app.css",
+      "!!**/node_modules"
+    ]
+  }
+}