fix(feedback): clone existing batch branch directly to prevent non-fast-forward push failure

[Copilot]

When a batch PR already exists, subsequent coordinate feedback submissions failed with "Could apply changes, please try again later" because the git push was rejected.

Proposed Change(s)

• clone_and_checkout in tmp_repo.rs always cloned main then ran git checkout -b <branch> main, creating a local branch that diverged from the existing remote batch branch. The push was rejected as non-fast-forward.
• Split clone_and_checkout into two dedicated methods in tmp_repo.rs:
  • clone_and_checkout_new_branch — clones main and creates a fresh branch from it (used when no batch PR exists yet)
  • clone_and_checkout_existing_branch — clones directly with --branch <name> to check out the already-existing remote branch (used when adding an edit to an existing batch PR), making the subsequent push a clean fast-forward

Checklist

• Documentation
  • I have updated the documentation
  • No need to update the documentation

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[CommanderStorm]

@copilot instead of the branch_is_new flag on clone_and_checkout, please just add another method to tmp_repo.rs, since the methods content entirely depends on this.

[Copilot]

@copilot instead of the branch_is_new flag on clone_and_checkout, please just add another method to tmp_repo.rs, since the methods content entirely depends on this.

Done in 4725916. clone_and_checkout is now split into clone_and_checkout_new_branch and clone_and_checkout_existing_branch, each with its own focused implementation. The branch_is_new flag is gone from tmp_repo.rs; mod.rs calls whichever method is appropriate.

[Copilot]

Pull request overview

Fixes feedback batching pushes by ensuring edits to an existing batch PR fast-forward cleanly, avoiding non-fast-forward rejections when the remote batch branch already exists.

Changes:

• Split TempRepo::clone_and_checkout into clone_and_checkout_new_branch and clone_and_checkout_existing_branch.
• Update feedback edit flow to choose the appropriate clone strategy depending on whether a batch PR already exists.
• Adjust existing tests to use the renamed “new branch” clone method.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
server/src/routes/feedback/proposed_edits/tmp_repo.rs	Adds separate clone/checkout paths for new vs. existing remote branches to avoid divergent histories.
server/src/routes/feedback/proposed_edits/mod.rs	Threads a branch_is_new flag into edit application to select the correct TempRepo clone method.