Show status and commit in trigger job show page

What does this MR do and why?

For #345046

!76115 (merged) sets up the bridge job show page, but the UI for it is static. This MR fetches the pipeline and job data so we can show the CI header and commit information on the page.

This page is hidden behind the :ci_retry_downstream_pipeline feature flag.

Technical Details

It might be easier to review this MR by going through the changes in each commit:

Commit	Summary
02bc8443	Fetch pipeline data
df0d19d1	Pass downstreamPipelinePath from rails
5b601be7	Move sidebar toggle logic to bridge app*
14672652	Add CI header and commit block

*The sidebar toggle logic originally resided in bridge/components/sidebar.vue. This is moved to the parent component bridge/app.vue since the sidebar can be toggled by both the sidebar component and the CI header component (see recording below).

Screenshots or screen recordings

Before	After

For comparison, this is what a regular job page looks like (a bridge page only shows information for a trigger job, so there should be no logs or artifacts). The stage dropdown and jobs list components will be added to the sidebar in a future MR.

Regular Job Page

Recording of the sidebar toggle behavior:

Sidebar toggle behavior

Sidebar Toggle

How to set up and validate locally

1. Enable the ci_retry_downstream_pipeline feature flag. (rails c then Feature.enable(:ci_retry_downstream_pipeline))
2. Add the following content to your .gitlab-ci.yml file:

   stages:
     - prepare
     - deploy
   
   job:
     stage: prepare
     script:
       - echo "running prepare_job"
   
   triggerJob:
     stage: deploy
     trigger:
       include:
         - project: "/path/to/project" # replace with another project
           file: ".gitlab-ci.yml"

3. Visit the pipeline and click on the triggerJob job pill.
4. Site should redirect to the trigger show page.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.