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

app/src/main/java/com/shaarit/presentation/nav/NavGraph.kt

@@ -58,6 +58,29 @@ fun AppNavGraph(
 ) {
     val navController = rememberNavController()
     val context = LocalContext.current
+    
+    // If user is already logged in and has share data, navigate directly to Add screen
+    val hasShareData = shareUrl != null || (isFileShare && shareTitle != null)
+    androidx.compose.runtime.LaunchedEffect(hasShareData) {
+        if (hasShareData && startDestination != Screen.Login.route) {
+            val route = if (isFileShare && shareTitle != null) {
+                val encodedTitle = URLEncoder.encode(shareTitle, "UTF-8")
+                val encodedDesc = if (shareDescription != null) URLEncoder.encode(shareDescription, "UTF-8") else ""
+                val encodedTags = shareTags?.joinToString(",") { URLEncoder.encode(it, "UTF-8") } ?: ""
+                "add?url=&title=$encodedTitle&isShare=true&isFileShare=true&description=$encodedDesc&tags=$encodedTags"
+            } else if (shareUrl != null) {
+                val encodedUrl = URLEncoder.encode(shareUrl, "UTF-8")
+                val encodedTitle = if (shareTitle != null) URLEncoder.encode(shareTitle, "UTF-8") else ""
+                "add?url=$encodedUrl&title=$encodedTitle&isShare=true&isFileShare=false&description=&tags="
+            } else null
+            
+            route?.let {
+                navController.navigate(it) {
+                    popUpTo(startDestination) { inclusive = true }
+                }
+            }
+        }
+    }
 
     NavHost(navController = navController, startDestination = startDestination) {
         composable(Screen.Login.route) {