Add debug logging via LogOutputChannel

[Copilot]

• Create centralized logger module (src/logger.ts) using vscode.LogOutputChannel
• Initialize logger in src/extension.ts during activation
• Replace existing console.error/console.warn calls with logger calls
• Add debug logging to extension lifecycle, commands, detection, documents, status bar, API client, notifications, MCP server, and task provider
• Add tests for the logger module
• Validate with lint, compile, and compile-tests
• Run code review and address feedback
• Run security scan (CodeQL) — no issues found
• Add changelog entry under [1.13.0] - Unreleased
• Add debug logging documentation to README troubleshooting section
• Fix 6 failing API client tests caused by closed LogOutputChannel throwing Error: Channel has been closed

Original prompt

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This section details on the original issue you should resolve

<issue_title>Adding debug logging</issue_title>
<issue_description>We should add debug logging to show in the Debug Console to help investigating issues.

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Adding debug logging #335

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[garrytrinder]

@copilot update this PR to include changelog and readme updates following the guidelines in AGENTS.md

[Copilot]

@copilot update this PR to include changelog and readme updates following the guidelines in AGENTS.md

Added in 5b365a3:

• CHANGELOG.md: new entry under [1.13.0] - Unreleased → Added for the debug logging feature
• README.md: added "View debug logs" guidance to the Troubleshooting section

[garrytrinder]

@copilot fix the failing tests

[Copilot]

@copilot fix the failing tests

Fixed in a900441. The 6 failing API client tests were caused by logger.debug() calls hitting a closed LogOutputChannel during test execution. Wrapped all logger function calls in try-catch blocks so they gracefully handle the Error: Channel has been closed case.