test: improve assertions in summary.rs and agentic_pipeline.rs (#1075)

- from_pipeline_round_trips_jobs_and_graph: add env_refs[0].name,
  condition_refs[0].step, condition_refs[0].name, and
  prod_step.outputs[0].name assertions (previously only counts /
  auto_is_output flag were checked, leaving regressions on which
  step/output is referenced invisible)
- serializes_to_json_without_panicking: rename to
  serialized_json_contains_schema_version_and_shape so the name
  reflects that it validates specific JSON fields, not merely that
  serialization doesn't panic
- fold_agent_conditions_preserves_clause_order: add diagnostic message
- parse_env_block_bails_on_malformed_yaml: correct comment — the
  invalid input has the stray ':' in the value, not in the key
- split_yaml_step_sequence_multiple_steps_without_blank_line_separator:
  add starts_with("- bash:") format checks for both chunks, matching
  the single-step sibling test

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

src/compile/agentic_pipeline.rs

@@ -2222,7 +2222,7 @@ mod tests {
         ];
         let cond = fold_agent_conditions(&clauses).unwrap();
         let Condition::And(parts) = cond else {
-            panic!()
+            panic!("expected And, got {cond:?}")
         };
         assert_eq!(parts.len(), 4);
         assert!(matches!(parts[0], Condition::Succeeded));
@@ -2255,9 +2255,10 @@ mod tests {
 
     #[test]
     fn parse_env_block_bails_on_malformed_yaml() {
-        // Stray `:` inside a bare key would make this fail to parse as
-        // a mapping. The previous silent `return Vec::new()` swallowed
-        // this — the typed Result surface should bail loudly.
+        // `KEY: : value` is ambiguous/invalid YAML: the bare value
+        // starts with `: `, which the YAML parser cannot interpret as
+        // a plain scalar.  Callers should never produce such a block,
+        // so the typed Result surface should bail loudly.
         let err = parse_env_block("env:\n  KEY: : value\n").unwrap_err();
         let msg = format!("{err:#}");
         assert!(
@@ -2303,6 +2304,8 @@ mod tests {
         let yaml = "- bash: echo first\n  displayName: First\n- bash: echo second\n  displayName: Second\n";
         let chunks = split_yaml_step_sequence(yaml).unwrap();
         assert_eq!(chunks.len(), 2, "got chunks: {chunks:?}");
+        assert!(chunks[0].starts_with("- bash:"), "chunk[0]: {}", chunks[0]);
+        assert!(chunks[1].starts_with("- bash:"), "chunk[1]: {}", chunks[1]);
         assert!(chunks[0].contains("First"));
         assert!(chunks[1].contains("Second"));
     }

src/compile/ir/summary.rs

@@ -705,7 +705,10 @@ mod tests {
         let step = &agent.steps[0];
         assert_eq!(step.env_refs.len(), 1);
         assert_eq!(step.env_refs[0].step, "synthPr");
+        assert_eq!(step.env_refs[0].name, "AW_SYNTHETIC_PR_ID");
         assert_eq!(step.condition_refs.len(), 1);
+        assert_eq!(step.condition_refs[0].step, "synthPr");
+        assert_eq!(step.condition_refs[0].name, "AW_SYNTHETIC_PR_ID");
         // Graph derived a job edge Agent -> Setup
         assert!(
             s.graph
@@ -715,14 +718,15 @@ mod tests {
             "expected derived edge Agent -> Setup, got {:?}",
             s.graph.job_edges
         );
-        // Producer output is marked auto_is_output
+        // Producer output is marked auto_is_output — verify it's the right output
         let setup = jobs.iter().find(|j| j.id == "Setup").unwrap();
         let prod_step = &setup.steps[0];
+        assert_eq!(prod_step.outputs[0].name, "AW_SYNTHETIC_PR_ID");
         assert!(prod_step.outputs[0].auto_is_output);
     }
 
     #[test]
-    fn serializes_to_json_without_panicking() {
+    fn serialized_json_contains_schema_version_and_shape() {
         let p = fixture_pipeline();
         let s = PipelineSummary::from_pipeline(&p).unwrap();
         let json = serde_json::to_string(&s).unwrap();