consider server commands finished vs requesting user input when appropriate

[meganrogge]

fixes #283902

Note this only works when isBackground is true as we only await command finished in that case. cc @Tyriar

Before, hanging or requesting input when we don't need it:

After:

[Copilot]

Pull request overview

This PR fixes an issue where the terminal command monitor would hang on non-interactive help prompts that don't actually require user input. The fix introduces a new pattern detection function to identify help prompts like "press h + enter to show help" and treats them as command completion rather than requesting user input.

Key changes:

• Added detectsNonInteractiveHelpPattern function to identify non-interactive help messages
• Integrated early checks in the monitoring pipeline to avoid unnecessary LLM consultations for help prompts
• Improved error handling when hiding prompt UI elements

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/vs/workbench/contrib/terminalContrib/chatAgentTools/browser/tools/monitoring/outputMonitor.ts	Implements the new detectsNonInteractiveHelpPattern function with regex patterns to detect help prompts, integrates checks in _waitForIdle, _handleIdleState, and _determineUserInputOptions to short-circuit on help messages, improves error handling for prompt hiding, and fixes output fallback logic
src/vs/workbench/contrib/terminalContrib/chatAgentTools/test/browser/outputMonitor.test.ts	Adds test case verifying help prompts complete without LLM consultation, adds comprehensive regex pattern tests for the new detection function, and exports the new function for testing