tests: Create MCP tool usage tests

[latekvo]

This PR adds tests for checking how keen AI is to use the MCP tools we provide in different scenarios.

Note: These tests are, and always will be flaky. This is unavoidable. The goal of these tests isn't to get 100% success rate, the goal is to improve the current success rate from ~33% to 70% or more.

How Has This Been Tested:

• Run command: Radon IDE: Test AI tool usage (id: RNIDE.testChatToolUsage)
• See results.

Collapsed example test results

=== AI TEST RESULTS ===
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
OK 
OK 
OK 
OK 
OK 
FAIL | Error: No tools were called.
FAIL | Error: No tools were called.
FAIL | Error: Expected: view_screenshot. Received: copilot_findTextInFiles, copilot_findTextInFiles, copilot_readFile, copilot_readFile, copilot_readFile
FAIL | Error: Expected: view_screenshot. Received: copilot_readFile
OK 
FAIL | Error: Expected: view_component_tree. Received: copilot_findTextInFiles
FAIL | Error: Expected: view_component_tree. Received: copilot_findTextInFiles
OK 
FAIL | Error: No tools were called.
FAIL | Error: Expected: view_component_tree | view_screenshot. Received: copilot_findTextInFiles, copilot_findTextInFiles, copilot_findTextInFiles, copilot_findTextInFiles, copilot_findTextInFiles, copilot_searchCodebase
# TOTAL CORRECT: 7/21 (33.3%)

How Has This Change Been Documented:

Does not apply (pretty sure)

[filip131311]

this should be a part of vscode-extension-tester and not the main extension