feat: Add local SQLite analytics tracking

- AnalyticsEvent: Data class for tracked events
- AnalyticsDao: Room DAO with CRUD operations
- AnalyticsDatabase: Room database singleton
- AnalyticsManager: High-level API for logging events
- Unit tests for AnalyticsEvent

Event types: page_view, session_start, session_end,
idle_reset, admin_access, config_sync, signage_rotate

Supports JSON/CSV export for admin panel integration.

app/build.gradle.kts

@@ -1,6 +1,7 @@
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
+    alias(libs.plugins.ksp)
 }
 
 android {
@@ -47,6 +48,11 @@ dependencies {
     implementation(libs.androidx.webkit)
     implementation(libs.androidx.datastore.preferences)
     
+    // Room for local analytics storage
+    implementation(libs.androidx.room.runtime)
+    implementation(libs.androidx.room.ktx)
+    ksp(libs.androidx.room.compiler)
+    
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.junit)
     androidTestImplementation(libs.androidx.espresso.core)