fix: use timestamp-based approach for inline suggestion visibility check

- Add lastVisibleTime property to CodeWhispererSession
- Update checkInlineSuggestionVisibility to record timestamp
- Replace try/catch with timestamp comparison in isCompletionActive
- Addresses Lei's concern about catch block never executing

Author: floralph

packages/amazonq/src/app/inline/completion.ts

@@ -249,12 +249,9 @@ export class AmazonQInlineCompletionItemProvider implements InlineCompletionItem
 
         // Use VS Code command to check if inline suggestion is actually visible on screen
         // This command only executes when inlineSuggestionVisible context is true
-        try {
-            await vscode.commands.executeCommand('aws.amazonq.checkInlineSuggestionVisibility')
-            return true
-        } catch {
-            return false
-        }
+        await vscode.commands.executeCommand('aws.amazonq.checkInlineSuggestionVisibility')
+        const isInlineSuggestionVisible = performance.now() - session.lastVisibleTime < 50
+        return isInlineSuggestionVisible
     }
 
     /**

packages/amazonq/src/app/inline/sessionManager.ts

@@ -26,6 +26,8 @@ export interface CodeWhispererSession {
     triggerOnAcceptance?: boolean
     // whether any suggestion in this session was displayed on screen
     displayed: boolean
+    // timestamp when the suggestion was last visible
+    lastVisibleTime: number
 }
 
 export class SessionManager {
@@ -52,6 +54,7 @@ export class SessionManager {
             firstCompletionDisplayLatency,
             diagnosticsBeforeAccept,
             displayed: false,
+            lastVisibleTime: 0,
         }
         this._currentSuggestionIndex = 0
     }
@@ -134,6 +137,7 @@ export class SessionManager {
     public checkInlineSuggestionVisibility() {
         if (this.activeSession) {
             this.activeSession.displayed = true
+            this.activeSession.lastVisibleTime = performance.now()
         }
     }