Add dates to release notes

Question

The `/release-notes` command output doesn't include dates for any of the versions. Adding release dates would help users understand the timeline of changes — e.g., how recent a fix is, or how long ago a feature was introduced.

Example of current format:
```
Version 2.1.56:
• VS Code: Fixed another cause of "command 'claude-vscode.editor.openLast' not found" crashes
```

Suggested format:
```
Version 2.1.56 (2025-07-15):
• VS Code: Fixed another cause of "command 'claude-vscode.editor.openLast'