Configure .gitignore to properly ignore build artifacts

- Add comprehensive Android/Gradle ignore patterns
- Ignore compiled output, dependencies, and sensitive files
- Remove tracked build artifacts from repository

app/build/outputs/apk/debug/output-metadata.json

@@ -1,20 +0,0 @@
-{
-  "version": 3,
-  "artifactType": {
-    "type": "APK",
-    "kind": "Directory"
-  },
-  "applicationId": "com.inspection.camera",
-  "variantName": "debug",
-  "elements": [
-    {
-      "type": "SINGLE",
-      "filters": [],
-      "attributes": [],
-      "versionCode": 1,
-      "versionName": "1.0",
-      "outputFile": "app-debug.apk"
-    }
-  ],
-  "elementType": "File"
-}