feat(media): add image/video/audio project kinds via od media generate

Introduce non-web media surfaces (image, video, audio) as first-class
project kinds. The unifying contract is "skill workflow + project
metadata tell the agent WHAT to make; one shell command — od media
generate — is HOW bytes are produced", so any code-agent CLI with
shell access can drive it without bespoke tools.

- Frontend: New Project panel gains Image/Video/Audio tabs with model
  picker, aspect/length/duration controls, and audio kind/voice
  selection. Examples and Design Systems tabs gain layered sections.
  FileViewer renders the generated image/video/audio files.
- Shared registry: src/media/models.ts is the single source of truth
  for image/video/audio model IDs, aspects, and defaults — consumed
  by the picker AND the daemon dispatcher.
- Prompts: media-contract.ts is pinned LAST in the system prompt for
  media surfaces so its hard rules (call od media generate, don't
  emit binary in <artifact>, allowed model IDs) win over softer
  earlier wording.
- Daemon: new media.js dispatcher + media-models.js JSON view of the
  registry; cli.js gets the `od media generate` subcommand wired up
  via server.js / projects.js so the daemon writes files back into
  the project dir.
- Skills: audio-jingle, image-poster, video-shortform seed examples
  for the three surfaces.

Made-with: Cursor

src/components/Icon.tsx

@@ -24,6 +24,8 @@ type IconName =
   | 'link'
   | 'mic'
   | 'minus'
+  | 'music'
+  | 'video'
   | 'pencil'
   | 'plus'
   | 'play'
@@ -232,6 +234,21 @@ export function Icon({ name, size = 14, strokeWidth = 1.6, ...rest }: Props) {
           <path d="M5 12h14" />
         </svg>
       );
+    case 'music':
+      return (
+        <svg {...common}>
+          <path d="M9 18V5l12-2v13" />
+          <circle cx="6" cy="18" r="3" />
+          <circle cx="18" cy="16" r="3" />
+        </svg>
+      );
+    case 'video':
+      return (
+        <svg {...common}>
+          <rect x="2" y="6" width="14" height="12" rx="2" />
+          <path d="m16 10 6-3v10l-6-3z" />
+        </svg>
+      );
     case 'pencil':
       return (
         <svg {...common}>