#Ieeesoc Fix diff view showing both "waiting for runtime" and diffs when agent is stopped Fixes #8061

[nhxe]

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• Include this change in the Release Notes.

End-user friendly description of the problem this fixes or functionality this introduces.
Fixes a bug in the diff viewer where stopping the agent caused both the "waiting for runtime" message and previously loaded diffs to appear simultaneously. The UI now correctly hides diffs when the agent is not running.

Summarize what the PR does, explaining any non-trivial design decisions.
This PR updates the GitChanges component to properly reflect the runtime state of the agent:

• Introduces an early return when the agent is inactive, ensuring only the "waiting for runtime" message is displayed.
• Prevents stale diffs from rendering when the runtime becomes inactive after diffs have been loaded.
• Adds default handling and type safety for edge cases like unknown or blank error messages.
• Improves key usage in diff list rendering for stability (key={${change.path}-${change.status}}).
• Uses filter(Boolean) to avoid rendering empty or falsy status messages.

These changes ensure a clearer and more consistent user experience in diff view handling, especially during runtime transitions.

Link of any specific issues this addresses:
Fixes #8061

[amanape]

You also have a package.json and package-lock.json in the root directory. Please remove them as we have the proper ones in the /frontend directory

[amanape]

This change will potentially break the translations. Even if they don't this change should be reverted for consistent naming

[amanape]

Please revert this change as we depend on React Router types here

[amanape]

This file is unrelated to the issue, please revert