fix(actions): show run index in run view and fix summary graph height (#38165)

- Display the per-repository run number as `#N` next to the run title in
the run view, matching the runs list and GitHub
- Add the run `Index` to the run view API response (and the devtest
mock) to support that
- Restore the summary panel's `flex: 1` so the workflow graph fills the
right-column height even when a run has no job summaries
- Keep the job-summary section content-sized so it doesn't compete with
the graph for height
- Gate the devtest mock job summaries to a subset of runs so the devtest
page also exercises the no-summary layout

<img width="521" height="232" alt="image"
src="https://github.com/user-attachments/assets/a1f2f20b-65bd-4d98-ba6a-b8135580a6de"
/>

web_src/js/components/ActionRunView.ts

@@ -107,6 +107,7 @@ export function buildJobsByParentJobID(jobs: ActionsJob[]): Map<number, ActionsJ
 export function createEmptyActionsRun(): ActionsRun {
   return {
     repoId: 0,
+    index: 0,
     link: '',
     viewLink: '',
     title: '',

web_src/js/components/RepoActionView.vue

@@ -141,6 +141,7 @@ onBeforeUnmount(() => {
           <ActionStatusIcon :locale-status="locale.status[run.status]" :status="run.status" :size="22" icon-variant="circle-fill"/>
           <!-- eslint-disable-next-line vue/no-v-html -->
           <h2 class="action-info-summary-title-text" v-html="run.titleHTML"/>
+          <span class="action-info-summary-title-index">#{{ run.index }}</span>
         </div>
         <div class="flex-text-block tw-shrink-0 tw-flex-wrap">
           <button class="ui basic small compact button primary" @click="approveRun()" v-if="run.canApprove">
@@ -377,10 +378,15 @@ onBeforeUnmount(() => {
 .action-info-summary-title-text {
   font-size: 20px;
   margin: 0;
-  flex: 1;
   overflow-wrap: anywhere;
 }
 
+.action-info-summary-title-index {
+  font-size: 20px;
+  color: var(--color-text-light-2);
+  flex: 1;
+}
+
 .action-info-summary .ui.button {
   margin: 0;
   white-space: nowrap;
@@ -497,6 +503,7 @@ onBeforeUnmount(() => {
 }
 
 .action-view-right-panel {
+  flex: 1; /* fill the right column so the summary graph stretches even without a job-summary section */
   border: 1px solid var(--color-console-border);
   border-radius: var(--border-radius);
   background: var(--color-console-bg);
@@ -538,6 +545,7 @@ onBeforeUnmount(() => {
 }
 
 .job-summary-section {
+  flex: 0 0 auto; /* size to its content; let the summary panel keep the remaining height */
   overflow: hidden;
 }
 

web_src/js/modules/gitea-actions.ts

@@ -4,6 +4,7 @@ export type ActionsArtifactStatus = 'expired' | 'completed';
 
 export type ActionsRun = {
   repoId: number,
+  index: number,
   link: string,
   viewLink: string,
   title: string,