fix(orchestrator): post adf/build commit status from handle_push dispatch

The build-runner spawned by handle_push had commit_status_post: None,
so no terminal status (success/failure) was ever posted to Gitea. This
meant branch protection context 'adf/build' never turned green and PRs
could never auto-merge.

Now sets commit_status_post to Some((after_sha, "adf/build")) and
posts a pending status at spawn time, matching the behaviour of
dispatch_build_runner_for_pr which already did this correctly.

Author: Alex

crates/terraphim_orchestrator/src/lib.rs

@@ -2753,10 +2753,19 @@ impl AgentOrchestrator {
                 mention_depth: None,
                 mention_parent_agent: None,
                 concurrency_permit: None,
-                commit_status_post: None,
+                commit_status_post: Some((after_sha.clone(), "adf/build".to_string())),
             },
         );
 
+        self.post_pending_status(
+            &after_sha,
+            0,
+            &project,
+            "adf/build",
+            "build-runner dispatched",
+        )
+        .await;
+
         info!(
             agent = %def.name,
             project = %project,