Bug: Editing an app resets branch to default

Read client/src/components/apps/form.vue, starting with loadPipelineAndApp() and the async loadBranches() and loadApp() calls around the referenced lines. Confirm that branch loading still populates branchesList, while editing preserves the saved branch and creating a new app selects the repository default; verify the create and edit flows in the Kubero UI.

Which component(s) is affected?

Kubero UI

Describe the bug

When editing an existing app that is configured to use a non-default branch (e.g. develop), the branch input field shows the repository's default branch (e.g. main) instead of the previously configured branch. If the user clicks "Save" without noticing, the app's branch is silently changed to the default — causing it to deploy from the wrong branch.

Steps to reproduce

1. Create a pipeline connected to a git repository with multiple branches (e.g. main, develop)
2. Create an app and set the branch to a non-default branch (e.g. develop)
3. Save the app
4. Navigate back to edit the same app
5. Observe: The branch field shows main (the default branch) instead of develop
6. Click "Save" without changing anything
7. Result: The app's branch is now changed to main

Expected behavior

When editing an existing app, the branch field should show the branch that was previously configured and saved.

Screenshots

No response

Additional information

Root Cause

The bug is a race condition in client/src/components/apps/form.vue between two unawaited async calls in loadPipelineAndApp() (line 1928):

1. Line 1936: this.loadBranches() fires an async HTTP request to /api/repo/.../branches (NOT awaited)
2. Line 2004: this.loadApp() fires an async HTTP request to /api/apps/... (NOT awaited)

Both .then() callbacks assign this.branch:

• loadApp() (line 2141) correctly sets this.branch = response.data.spec.branch (the saved value, e.g. "develop")
• loadBranches() (lines 2037–2042) unconditionally overwrites this.branch with pipelineData.git.repository.default_branch (e.g. "main")

Since loadBranches() calls an external git provider API (GitHub/GitLab/etc.), it is typically slower than loadApp() (which hits the local Kubernetes API). So the usual execution order is:

1. loadApp() resolves first → sets this.branch = "develop" ✅
2. loadBranches() resolves second → overwrites this.branch = "main" ❌

Suggested Fix

Guard the branch assignment in loadBranches() so it only pre-selects a default branch when creating a new app:

// In loadBranches(), lines 2036-2042:
if (this.app == "new") {
  let defaultBranch = this.pipelineData.git.repository.default_branch;
  if (this.branchesList.includes(defaultBranch)) {
    this.branch = defaultBranch;
  } else {
    this.branch = this.branchesList[0];
  }
}

This ensures loadBranches() still populates the branchesList dropdown (needed for both create and edit), but only pre-selects a branch value during app creation. During edit, loadApp() retains the final say on this.branch.

Additional Context

• The server side correctly stores and returns spec.branch from the KuberoApp CRD — no issue there
• The kubero-operator (Helm-based) passes spec.branch through to deployment templates without modification — no issue there
• The bug is purely a frontend race condition

Debug information

No response