remove diff logs

[ianjennings]

Removes these logs:

New content preview: version: 6.0.23
session: 68ace3e0f3b07efd8ae36e2a
steps:
  - prompt: assert app opens
    commands:

Creating diff - content has changed
Checking for diff. File exists: true
Content changed: true
Existing content preview: version: 6.0.23
session: 68ace3e0f3b07efd8ae36e2a
steps:
  - prompt: assert app opens
    commands:

New content preview: version: 6.0.23
session: 68ace3e0f3b07efd8ae36e2a
steps:
  - prompt: assert app opens
    commands:

Creating diff - content has changed

[Copilot]

Pull Request Overview

This PR removes debug logging statements related to diff operations in the agent/index.js file. The changes clean up console output by removing verbose logging that was likely used during development or debugging of the file comparison and diff generation functionality.

Key changes:

• Removes console logs for file existence and content change checks
• Eliminates debug output showing content previews and diff creation status
• Removes unnecessary logging for cases where no diff result is generated

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[Copilot]

The else block at line 1231 appears to be empty after removing the console.log statement. Consider removing the entire else block if it serves no purpose.