Feature: Customizable automatic repository refresh interval

[pacificleo]

Is your feature request related to a problem? Please describe.

Currently, the automatic repository refresh interval (which sweeps for GitHub PR updates and SSH remote branch changes) is hardcoded to 5 minutes (.seconds(300)). While background polling can be disabled entirely, users cannot adjust the frequency. Some users hitting GitHub API rate limits or excessive SSH passphrase prompts may wish to reduce the polling frequency, while others may want more aggressive updates.

Describe the solution you'd like

I would like to expose automaticRepositoryRefreshInterval in the Worktree settings as a customizable text field. It should default to 5 minutes (to preserve current behavior) but allow the user to input any number of minutes.

When the setting is updated, WorktreeInfoWatcherManager should dynamically tear down its existing loop and restart it with the new interval without requiring an app restart.

Describe alternatives you've considered

No response

Are you planning to implement this yourself?

• I intend to open a pull request once this is confirmed and marked ready.

Before submitting

• I searched existing issues and this is not a duplicate.
• I understand pull requests are closed until the issue is marked ready.
• I agree to follow this project's Code of Conduct.

[github-actions]

Thank you for filing this. A maintainer will review it and follow up here.

Please do not start any work or open a pull request until this issue is labeled ready. That label is a maintainer's go-ahead: a pull request opened against an issue that is not yet ready is labeled invalid until then. You will get a comment here the moment it is marked ready.

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