docs: Update comprehensive documentation with AI features, health checks, and architecture improvements

- Document automatic token verification on startup and note:// prefix for Markdown notes
- Add extensive AI capabilities section (Gemini integration, auto-tagging, content classification, multi-model fallback)
- Document link health monitoring system with dead link detection and exclusion features
- Add file sharing support (Markdown/text files) and deep links documentation
- Update technology

gradle/libs.versions.toml

@@ -24,6 +24,7 @@ workManager = "2.9.0"
 dataStore = "1.0.0"
 kotlinxSerialization = "1.6.2"
 coil = "2.6.0"
+biometric = "1.1.0"
 
 [libraries]
 material = { group = "com.google.android.material", name = "material", version.ref = "material" }
@@ -83,6 +84,9 @@ coil-compose = { group = "io.coil-kt", name = "coil-compose", version.ref = "coi
 # Kotlin Serialization
 kotlinx-serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version.ref = "kotlinxSerialization" }
 
+# Biometric
+androidx-biometric = { group = "androidx.biometric", name = "biometric", version.ref = "biometric" }
+
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 jetbrains-kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }