fix: allow new tasks to bypass queued messages and add clear all button

[roomote]

This PR attempts to address Issue #9015 where queued messages were blocking the entire conversation.

Problem

Users reported that when messages get queued, they cannot:

• Delete queued messages (actually this was already possible via individual delete buttons)
• Edit queued messages (actually this was already possible by clicking on them)
• Start new tasks (this was the main issue - queued messages blocked all interaction)

Solution

1. Allow new tasks to bypass the queue: Modified ChatView.tsx to detect when a user is starting a new task (no existing messages) and allow it to proceed even when there are queued messages.

2. Added "Clear All" button: Enhanced the QueuedMessages component with a bulk delete option to clear all queued messages at once.

Changes

• Modified ChatView.tsx to check if this is a new task and bypass queue restrictions
• Added "Clear All" button to QueuedMessages.tsx component
• Implemented clearAll() method in MessageQueueService
• Added webview message handler for clearQueuedMessages
• Updated WebviewMessage type definitions

Testing

• TypeScript compilation passes
• All existing tests pass
• Linting passes

Fixes #9015

Feedback and guidance are welcome!

---

Important

Allows new tasks to bypass queued messages and adds a "Clear All" button to clear queued messages in ChatView.tsx and QueuedMessages.tsx.

• Behavior:
  • ChatView.tsx: Allows new tasks to bypass queued messages by checking if there are no existing messages.
  • QueuedMessages.tsx: Adds a "Clear All" button to remove all queued messages at once.
• Functions:
  • clearAll() in MessageQueueService.ts: Clears all messages and emits a state change.
  • webviewMessageHandler.ts: Handles clearQueuedMessages to invoke clearAll().
• Types:
  • WebviewMessage.ts: Adds clearQueuedMessages to WebviewMessage type.
• Testing:
  • TypeScript compilation, existing tests, and linting pass.

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[roomote]

Review Complete

No issues found. The implementation correctly addresses the queued message blocking problem:

• New task bypass logic properly checks message history length
• Clear All button integration is clean and functional
• Backend service changes are minimal and correct
• Type definitions properly updated

The PR successfully resolves issue #9015.

_{Mention @roomote in a comment to trigger your PR Fixer agent and make changes to this pull request.}

[ellipsis-dev]

Remove inline fallback string in the translation call. Use translation keys defined in external language files rather than providing 'Clear All' as a fallback inline.

Suggested change

	{t("queuedMessages.clearAll", "Clear All")}
	{t("queuedMessages.clearAll")}

^{This comment was generated because it violated a code review rule: irule_C0ez7Rji6ANcGkkX.}