Replace index with id in actions routes (#36842)

This PR migrates the web Actions run/job routes from index-based
`runIndex` or `jobIndex` to database IDs.

**⚠️ BREAKING ⚠️**: Existing saved links/bookmarks that use the old
index-based URLs will no longer resolve after this change.

Improvements of this change:
- Previously, `jobIndex` depended on list order, making it hard to
locate a specific job. Using `jobID` provides stable addressing.
- Web routes now align with API, which already use IDs.
- Behavior is closer to GitHub, which exposes run/job IDs in URLs.
- Provides a cleaner base for future features without relying on list
order.
- #36388 this PR improves the support for reusable workflows. If a job
uses a reusable workflow, it may contain multiple child jobs, which
makes relying on job index to locate a job much more complicated

---------

Signed-off-by: Zettat123 <zettat123@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

routers/web/devtest/mock_actions.go

@@ -59,8 +59,8 @@ func generateMockStepsLog(logCur actions.LogCursor, opts generateMockStepsLogOpt
 }
 
 func MockActionsView(ctx *context.Context) {
-	ctx.Data["RunIndex"] = ctx.PathParam("run")
-	ctx.Data["JobIndex"] = ctx.PathParam("job")
+	ctx.Data["RunID"] = ctx.PathParam("run")
+	ctx.Data["JobID"] = ctx.PathParam("job")
 	ctx.HTML(http.StatusOK, "devtest/repo-action-view")
 }