Rationalize config file locations and update documentation

internal/app/commands_test.go

@@ -12,6 +12,7 @@ import (
 	"testing"
 	"time"
 
+	"gitea.maximumdirect.net/eric/narratio/internal/config"
 	"gitea.maximumdirect.net/eric/narratio/internal/manifest"
 )
 
@@ -63,12 +64,13 @@ func TestExecuteMissingRequiredFlags(t *testing.T) {
 		args []string
 		want string
 	}{
-		{name: "run missing flags", args: []string{"run"}, want: "run: --config and --session are required"},
-		{name: "plan missing flags", args: []string{"plan"}, want: "plan: --config and --session are required"},
+		{name: "run missing flags", args: []string{"run"}, want: "run: --session is required"},
+		{name: "plan missing flags", args: []string{"plan"}, want: "plan: --session is required"},
 		{name: "status missing flags", args: []string{"status"}, want: "status: --manifest is required"},
-		{name: "resume missing flags", args: []string{"resume"}, want: "resume: --config and --session are required"},
+		{name: "resume missing flags", args: []string{"resume"}, want: "resume: --session is required"},
 		{name: "run-stage missing name", args: []string{"run-stage", "--config", "a", "--session", "b"}, want: "run-stage: expected exactly one stage name"},
-		{name: "run-stage missing config flags", args: []string{"run-stage", "polish"}, want: "run-stage: --config and --session are required"},
+		{name: "run-stage missing config flags", args: []string{"run-stage", "polish"}, want: "run-stage: --session is required"},
+		{name: "run missing config uses defaults", args: []string{"run", "--session", "session.yml"}, want: "run: no pipeline config path provided and no default pipeline config found; searched:"},
 	}
 
 	for _, tc := range cases {
@@ -168,6 +170,32 @@ func TestExecuteRunStageTranscribeUsesConfiguredWhisperXServer(t *testing.T) {
 	}
 }
 
+func TestExecuteUsesDefaultPipelineConfigPathWhenConfigFlagOmitted(t *testing.T) {
+	workspaceRoot := t.TempDir()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"source":"default-config-test","segments":[{"speaker":"alice"}]}`))
+	}))
+	defer srv.Close()
+
+	pipelinePath, sessionPath := writeValidConfigFiles(t, workspaceRoot, srv.URL)
+	originalDefaults := append([]string(nil), config.DefaultPipelineConfigSearchPaths...)
+	config.DefaultPipelineConfigSearchPaths = []string{pipelinePath}
+	defer func() {
+		config.DefaultPipelineConfigSearchPaths = originalDefaults
+	}()
+
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	code := Execute([]string{"run", "--session", sessionPath}, &stdout, &stderr)
+	if code != 0 {
+		t.Fatalf("exit code = %d, want 0; stderr=%q", code, stderr.String())
+	}
+	if !strings.Contains(stdout.String(), "narratio run: session 2026-05-03; executed=9 skipped=0; manifest=") {
+		t.Fatalf("stdout = %q, want successful run output", stdout.String())
+	}
+}
+
 func TestExecuteInvalidCommand(t *testing.T) {
 	var stdout bytes.Buffer
 	var stderr bytes.Buffer