New videogen/ contract package (ADR-0019): Request/Result/Model/Provider
with the imagegen conventions. Text-to-video and image-to-video are one
surface (Request.InitImage, nil = t2v) since hybrid checkpoints like
Wan 2.2 TI2V serve both from one model; Result carries a single clip.

provider/llamaswap gains VideoModel(id) targeting the blocking
POST {base}/v1/videos/sync (multipart, model-routed by the fork's new
video routes): vLLM-Omni parameter names, OpenAI-style input_reference
file part, optional fields stay off the wire so per-model launch-flag
defaults apply. CLAUDE.md package map picks up audio/ (missed in #12)
and videogen/.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AXQxVhXBw8PwFAtsVrXSmj

@@ -0,0 +45,4 @@
+// entirely so the model's own defaults apply.
+func (m *videoModel) Generate(ctx context.Context, req videogen.Request, opts ...videogen.Option) (*videogen.Result, error) {
+	req = req.Apply(opts...)
+	if strings.TrimSpace(req.Prompt) == "" {

@@ -0,0 +59,4 @@
+	}
+	width, height, err := parseSize(req.Size)
+	if err != nil {
+		return nil, fmt.Errorf("%w: %v", llm.ErrUnsupported, err)

@@ -0,0 +79,4 @@
+		{"fps", formatNonZero(req.FPS), false},
+		{"num_inference_steps", formatInt(req.Steps), false},
+		{"guidance_scale", formatFloat(req.GuidanceScale), false},
+		{"seed", formatInt64(req.Seed), false},

@@ -0,0 +97,4 @@
+		if _, err := fw.Write(req.InitImage.Data); err != nil {
+			return nil, fmt.Errorf("llama-swap: build video form: %w", err)
+		}
+	}

@@ -0,0 +102,4 @@
+		return nil, fmt.Errorf("llama-swap: build video form: %w", err)
+	}
+
+	videoBytes, contentType, err := m.p.doRaw(ctx, http.MethodPost, "/v1/videos/sync", m.id, w.FormDataContentType(), &buf)

@@ -0,0 +119,4 @@
+	if mt, _, err := mime.ParseMediaType(contentType); err == nil && strings.HasPrefix(mt, "video/") {
+		return mt
+	}
+	if mt := http.DetectContentType(data); strings.HasPrefix(mt, "video/") {

@@ -0,0 +138,4 @@
+		return "frame.jpg"
+	case "image/webp":
+		return "frame.webp"
+	default: // stable-diffusion outputs and unknowns: PNG is the safe hint

@@ -0,0 +21,4 @@
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotPath = r.URL.Path
+		gotContentType = r.Header.Get("Content-Type")
+		if err := r.ParseMultipartForm(32 << 20); err != nil {

@@ -0,0 +103,4 @@
+	defer srv.Close()
+
+	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
+	vm, _ := p.VideoModel("videogen-wan")