test(cmd/ao): replace defer/t.Cleanup os.Chdir with t.Chdir (6 sites, 3 files)

Generator-layer test hygiene cycle. Continues the t.Chdir migration started
in PR #177 (which covered 5 cmd/ao test files: plans, dedup, config,
metrics_flywheel, metrics_health). This cycle picks up disjoint files so
PR #177 and this nightly do not conflict on the same _test.go.

Files migrated (6 sites):
- batch_forge_test.go (3 sites): TestRunForgeBatch_NoPendingTranscripts,
  TestRunForgeBatch_DryRunAppliesMaxLimit, TestRunForgeBatch_ProcessesTranscript.
  In each, replaces the 4-line block `origDir, err := os.Getwd(); ...
  os.Chdir(tmpDir); ...; t.Cleanup(func() { _ = os.Chdir(origDir) })`
  with `t.Chdir(tmpDir)`. Subsequent `err = runForgeBatch(...)` becomes
  `err := runForgeBatch(...)` (the prior implicit declaration came from
  the os.Getwd line).
- batch_promote_test.go (1 site): TestRunBatchPromote_NoPendingCandidates,
  same pattern.
- cobra_commands_test.go (2 sites): TestCobraStatusCommand/json_not_initialized
  and TestCobraSeedCommand. Pattern is the simpler `defer func() { _ =
  os.Chdir(orig) }()` form; collapses to `t.Chdir(...)`.

Net: -32 lines, +0 logic change. `go test -count=1 ./cmd/ao/...` passes;
`go vet ./...` clean; pre-push fast gate passes; full goals measure
unchanged (17 pass / 2 fail — the two open-state failures are
flywheel-compounding W=8 corpus-bound and go-complexity-ceiling W=6
in-flight via PR #177).

Author: claude

cli/cmd/ao/batch_forge_test.go

@@ -494,14 +494,7 @@ func TestLoadAndFilterTranscripts_RespectsForgedIndex(t *testing.T) {
 
 func TestRunForgeBatch_NoPendingTranscripts(t *testing.T) {
 	tmpDir := t.TempDir()
-	origDir, err := os.Getwd()
-	if err != nil {
-		t.Fatalf("getwd: %v", err)
-	}
-	if err := os.Chdir(tmpDir); err != nil {
-		t.Fatalf("chdir: %v", err)
-	}
-	t.Cleanup(func() { _ = os.Chdir(origDir) })
+	t.Chdir(tmpDir)
 
 	oldBatchDir, oldBatchMax, oldBatchExtract := batchDir, batchMax, batchExtract
 	oldOutput := output
@@ -521,7 +514,7 @@ func TestRunForgeBatch_NoPendingTranscripts(t *testing.T) {
 	origStdout := os.Stdout
 	r, w, _ := os.Pipe()
 	os.Stdout = w
-	err = runForgeBatch(nil, nil)
+	err := runForgeBatch(nil, nil)
 	w.Close()
 	os.Stdout = origStdout
 	if err != nil {
@@ -538,14 +531,7 @@ func TestRunForgeBatch_NoPendingTranscripts(t *testing.T) {
 
 func TestRunForgeBatch_DryRunAppliesMaxLimit(t *testing.T) {
 	tmpDir := t.TempDir()
-	origDir, err := os.Getwd()
-	if err != nil {
-		t.Fatalf("getwd: %v", err)
-	}
-	if err := os.Chdir(tmpDir); err != nil {
-		t.Fatalf("chdir: %v", err)
-	}
-	t.Cleanup(func() { _ = os.Chdir(origDir) })
+	t.Chdir(tmpDir)
 
 	transcriptDir := filepath.Join(tmpDir, "transcripts")
 	if err := os.MkdirAll(transcriptDir, 0o755); err != nil {
@@ -602,14 +588,7 @@ func TestRunForgeBatch_DryRunAppliesMaxLimit(t *testing.T) {
 
 func TestRunForgeBatch_ProcessesTranscript(t *testing.T) {
 	tmpDir := t.TempDir()
-	origDir, err := os.Getwd()
-	if err != nil {
-		t.Fatalf("getwd: %v", err)
-	}
-	if err := os.Chdir(tmpDir); err != nil {
-		t.Fatalf("chdir: %v", err)
-	}
-	t.Cleanup(func() { _ = os.Chdir(origDir) })
+	t.Chdir(tmpDir)
 
 	transcriptDir := filepath.Join(tmpDir, "transcripts")
 	if err := os.MkdirAll(transcriptDir, 0o755); err != nil {

cli/cmd/ao/batch_promote_test.go

@@ -389,14 +389,7 @@ func TestOutputBatchResult(t *testing.T) {
 
 func TestRunBatchPromote_NoPendingCandidates(t *testing.T) {
 	tmpDir := t.TempDir()
-	origDir, err := os.Getwd()
-	if err != nil {
-		t.Fatalf("getwd: %v", err)
-	}
-	if err := os.Chdir(tmpDir); err != nil {
-		t.Fatalf("chdir: %v", err)
-	}
-	t.Cleanup(func() { _ = os.Chdir(origDir) })
+	t.Chdir(tmpDir)
 
 	oldOutput := output
 	output = "text"
@@ -413,7 +406,7 @@ func TestRunBatchPromote_NoPendingCandidates(t *testing.T) {
 	origStdout := os.Stdout
 	r, w, _ := os.Pipe()
 	os.Stdout = w
-	err = runBatchPromote(nil, nil)
+	err := runBatchPromote(nil, nil)
 	w.Close()
 	os.Stdout = origStdout
 	if err != nil {

cli/cmd/ao/cobra_commands_test.go

@@ -585,9 +585,7 @@ func TestCobraStatusCommand(t *testing.T) {
 
 	t.Run("json_not_initialized", func(t *testing.T) {
 		tmp2 := t.TempDir()
-		orig, _ := os.Getwd()
-		_ = os.Chdir(tmp2)
-		defer func() { _ = os.Chdir(orig) }()
+		t.Chdir(tmp2)
 
 		// Reset the output flag
 		output = "json"
@@ -2336,9 +2334,7 @@ func TestCobraQuickstartHelpers(t *testing.T) {
 			t.Fatal(err)
 		}
 
-		orig, _ := os.Getwd()
-		_ = os.Chdir(tmp)
-		defer func() { _ = os.Chdir(orig) }()
+		t.Chdir(tmp)
 
 		// Capture stdout
 		old := os.Stdout