chore: update env example and gitignore, add implementation plan

- Update .env.example with documentation and default values
- Add .resources to gitignore (dummy test files)
- Add APK parsing fix implementation plan document

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

.env.example

@@ -1,3 +1,9 @@
-AUTH_USERNAME=
-AUTH_PASSWORD=
-RESOURCE_PATH=
+# Authentication credentials (change in production!)
+AUTH_USERNAME=admin
+AUTH_PASSWORD=changeme
+
+# Path to APK storage directory
+RESOURCE_PATH=./resources
+
+# Comma-separated list of tab names for APK filtering
+APK_TABS=dev,sandbox