Add render artifact model, config, and Seriatim adapter contracts

internal/adapters/seriatim/fake.go

@@ -68,6 +68,26 @@ func (n *NoopRunner) Normalize(ctx context.Context, req NormalizeRequest) (Norma
 	}, nil
 }
 
+// Render returns the requested output path with placeholder metadata.
+func (n *NoopRunner) Render(ctx context.Context, req RenderRequest) (RenderResult, error) {
+	if err := ctx.Err(); err != nil {
+		return RenderResult{}, err
+	}
+	if err := materializeRenderPlaceholders(req); err != nil {
+		return RenderResult{}, err
+	}
+	return RenderResult{
+		OutputRenderedPath:  req.OutputRenderedPath,
+		StdoutLogPath:       req.StdoutLogPath,
+		StderrLogPath:       req.StderrLogPath,
+		GeneratedConfigPath: req.GeneratedConfigPath,
+		InvokedBinary:       "noop",
+		Format:              req.Format,
+		Title:               req.Title,
+		Metadata:            map[string]any{"placeholder": true},
+	}, nil
+}
+
 // FakeRunner captures merge requests and returns deterministic responses.
 type FakeRunner struct {
 	Requests          []MergeRequest
@@ -79,6 +99,9 @@ type FakeRunner struct {
 	TrimRequests      []TrimRequest
 	TrimErr           error
 	TrimResult        TrimResult
+	RenderRequests    []RenderRequest
+	RenderErr         error
+	RenderResult      RenderResult
 }
 
 // Run records request and returns configured response.
@@ -195,6 +218,46 @@ func (f *FakeRunner) Normalize(ctx context.Context, req NormalizeRequest) (Norma
 	return res, nil
 }
 
+// Render records request and returns configured response.
+func (f *FakeRunner) Render(ctx context.Context, req RenderRequest) (RenderResult, error) {
+	if err := ctx.Err(); err != nil {
+		return RenderResult{}, err
+	}
+	f.RenderRequests = append(f.RenderRequests, req)
+	if f.RenderErr != nil {
+		return RenderResult{}, f.RenderErr
+	}
+	if err := materializeRenderPlaceholders(req); err != nil {
+		return RenderResult{}, err
+	}
+	res := f.RenderResult
+	if res.OutputRenderedPath == "" {
+		res.OutputRenderedPath = req.OutputRenderedPath
+	}
+	if res.StdoutLogPath == "" {
+		res.StdoutLogPath = req.StdoutLogPath
+	}
+	if res.StderrLogPath == "" {
+		res.StderrLogPath = req.StderrLogPath
+	}
+	if res.GeneratedConfigPath == "" {
+		res.GeneratedConfigPath = req.GeneratedConfigPath
+	}
+	if res.InvokedBinary == "" {
+		res.InvokedBinary = "fake"
+	}
+	if res.Format == "" {
+		res.Format = req.Format
+	}
+	if res.Title == "" {
+		res.Title = req.Title
+	}
+	if res.Metadata == nil {
+		res.Metadata = map[string]any{"fake": true}
+	}
+	return res, nil
+}
+
 func materializePlaceholders(req MergeRequest) error {
 	if req.OutputMergedTranscriptPath != "" {
 		if err := subprocess.WriteFileAtomic(req.OutputMergedTranscriptPath, []byte(`{"schema":"seriatim.intermediate.v1","segments":[]}`), 0o644); err != nil {
@@ -301,3 +364,39 @@ func materializeNormalizePlaceholders(req NormalizeRequest) error {
 	}
 	return nil
 }
+
+func materializeRenderPlaceholders(req RenderRequest) error {
+	if req.OutputRenderedPath != "" {
+		if err := subprocess.WriteFileAtomic(req.OutputRenderedPath, []byte("# Transcript\n\nRendered markdown placeholder.\n"), 0o644); err != nil {
+			return fmt.Errorf("write rendered transcript %q: %w", req.OutputRenderedPath, err)
+		}
+	}
+	if req.GeneratedConfigPath != "" {
+		payload := map[string]any{
+			"schema":              "seriatim.generated.v1",
+			"placeholder":         true,
+			"command":             "render",
+			"input_path":          req.InputTranscriptPath,
+			"output_path":         req.OutputRenderedPath,
+			"format":              req.Format,
+			"title":               req.Title,
+			"include_timestamps":  req.IncludeTimestamps,
+			"include_segment_ids": req.IncludeSegmentIDs,
+			"include_metadata":    req.IncludeMetadata,
+		}
+		if err := subprocess.WriteYAMLAtomic(req.GeneratedConfigPath, payload, 0o644); err != nil {
+			return fmt.Errorf("write generated config %q: %w", req.GeneratedConfigPath, err)
+		}
+	}
+	if req.StdoutLogPath != "" {
+		if err := subprocess.WriteFileAtomic(req.StdoutLogPath, []byte("seriatim noop/fake render stdout placeholder\n"), 0o644); err != nil {
+			return fmt.Errorf("write stdout log %q: %w", req.StdoutLogPath, err)
+		}
+	}
+	if req.StderrLogPath != "" {
+		if err := subprocess.WriteFileAtomic(req.StderrLogPath, []byte("seriatim noop/fake render stderr placeholder\n"), 0o644); err != nil {
+			return fmt.Errorf("write stderr log %q: %w", req.StderrLogPath, err)
+		}
+	}
+	return nil
+}