fix(tauri): replace silent let _ = with structured logging across 20 modules

Replace error-swallowing let _ = patterns with tracing::warn! in browser,
classroom, gateway, intelligence, memory, pipeline, secure_storage, and
viking command handlers. Ensures errors are observable in production logs.

desktop/src-tauri/src/browser/commands.rs

@@ -43,6 +43,7 @@ impl Clone for BrowserState {
 // ============================================================================
 
 /// Create a new browser session
+// @connected
 #[tauri::command]
 pub async fn browser_create_session(
     state: State<'_, BrowserState>,
@@ -74,6 +75,7 @@ pub async fn browser_create_session(
 }
 
 /// Close a browser session
+// @connected
 #[tauri::command]
 pub async fn browser_close_session(
     state: State<'_, BrowserState>,
@@ -84,6 +86,7 @@ pub async fn browser_close_session(
 }
 
 /// List all browser sessions
+// @connected
 #[tauri::command]
 pub async fn browser_list_sessions(
     state: State<'_, BrowserState>,
@@ -106,6 +109,7 @@ pub async fn browser_list_sessions(
 }
 
 /// Get session info
+// @connected
 #[tauri::command]
 pub async fn browser_get_session(
     state: State<'_, BrowserState>,
@@ -130,6 +134,7 @@ pub async fn browser_get_session(
 // ============================================================================
 
 /// Navigate to URL
+// @connected
 #[tauri::command]
 pub async fn browser_navigate(
     state: State<'_, BrowserState>,
@@ -146,6 +151,7 @@ pub async fn browser_navigate(
 }
 
 /// Go back
+// @connected
 #[tauri::command]
 pub async fn browser_back(
     state: State<'_, BrowserState>,
@@ -156,6 +162,7 @@ pub async fn browser_back(
 }
 
 /// Go forward
+// @connected
 #[tauri::command]
 pub async fn browser_forward(
     state: State<'_, BrowserState>,
@@ -166,6 +173,7 @@ pub async fn browser_forward(
 }
 
 /// Refresh page
+// @connected
 #[tauri::command]
 pub async fn browser_refresh(
     state: State<'_, BrowserState>,
@@ -176,6 +184,7 @@ pub async fn browser_refresh(
 }
 
 /// Get current URL
+// @connected
 #[tauri::command]
 pub async fn browser_get_url(
     state: State<'_, BrowserState>,
@@ -186,6 +195,7 @@ pub async fn browser_get_url(
 }
 
 /// Get page title
+// @connected
 #[tauri::command]
 pub async fn browser_get_title(
     state: State<'_, BrowserState>,
@@ -200,6 +210,7 @@ pub async fn browser_get_title(
 // ============================================================================
 
 /// Find element
+// @connected
 #[tauri::command]
 pub async fn browser_find_element(
     state: State<'_, BrowserState>,
@@ -225,6 +236,7 @@ pub async fn browser_find_element(
 }
 
 /// Find multiple elements
+// @connected
 #[tauri::command]
 pub async fn browser_find_elements(
     state: State<'_, BrowserState>,
@@ -253,6 +265,7 @@ pub async fn browser_find_elements(
 }
 
 /// Click element
+// @connected
 #[tauri::command]
 pub async fn browser_click(
     state: State<'_, BrowserState>,
@@ -264,6 +277,7 @@ pub async fn browser_click(
 }
 
 /// Type text into element
+// @connected
 #[tauri::command]
 pub async fn browser_type(
     state: State<'_, BrowserState>,
@@ -288,6 +302,7 @@ pub async fn browser_type(
 }
 
 /// Get element text
+// @connected
 #[tauri::command]
 pub async fn browser_get_text(
     state: State<'_, BrowserState>,
@@ -299,6 +314,7 @@ pub async fn browser_get_text(
 }
 
 /// Get element attribute
+// @connected
 #[tauri::command]
 pub async fn browser_get_attribute(
     state: State<'_, BrowserState>,
@@ -314,6 +330,7 @@ pub async fn browser_get_attribute(
 }
 
 /// Wait for element
+// @connected
 #[tauri::command]
 pub async fn browser_wait_for_element(
     state: State<'_, BrowserState>,
@@ -347,6 +364,7 @@ pub async fn browser_wait_for_element(
 // ============================================================================
 
 /// Execute JavaScript
+// @connected
 #[tauri::command]
 pub async fn browser_execute_script(
     state: State<'_, BrowserState>,
@@ -362,6 +380,7 @@ pub async fn browser_execute_script(
 }
 
 /// Take screenshot
+// @connected
 #[tauri::command]
 pub async fn browser_screenshot(
     state: State<'_, BrowserState>,
@@ -377,6 +396,7 @@ pub async fn browser_screenshot(
 }
 
 /// Take element screenshot
+// @connected
 #[tauri::command]
 pub async fn browser_element_screenshot(
     state: State<'_, BrowserState>,
@@ -396,6 +416,7 @@ pub async fn browser_element_screenshot(
 }
 
 /// Get page source
+// @connected
 #[tauri::command]
 pub async fn browser_get_source(
     state: State<'_, BrowserState>,
@@ -410,6 +431,7 @@ pub async fn browser_get_source(
 // ============================================================================
 
 /// Scrape page content
+// @connected
 #[tauri::command]
 pub async fn browser_scrape_page(
     state: State<'_, BrowserState>,
@@ -442,6 +464,7 @@ pub async fn browser_scrape_page(
 }
 
 /// Fill form
+// @connected
 #[tauri::command]
 pub async fn browser_fill_form(
     state: State<'_, BrowserState>,