feat(registry): bring back the video-primitive moves (#3169)

Restores the 208 catalog items reverted after their previews 404'd in
production, this time on the payload mechanism rather than the .html files
that caused the outage.

The generator no longer writes a preview document to docs/public. That writer,
and the machinery under it, existed only to produce files the docs host
discards, so it is gone rather than bypassed. Items now embed the composition
itself via a payload, which is what the previous change already does for the
items that were already in the catalog.

The variables explorer is parked, not restored: it drove its preview through
the same unpublished .html path, so it would have shown an empty frame. Items
that declare variables get the live player plus the static variables table, and
reconnecting the explorer to payloads is a follow-up.

registry/components/telemetry-hud/registry-item.json

@@ -0,0 +1,75 @@
+{
+  "$schema": "https://hyperframes.heygen.com/schema/registry-item.json",
+  "name": "telemetry-hud",
+  "type": "hyperframes:component",
+  "title": "Telemetry HUD",
+  "description": "Quiet mono debug-HUD readouts frame a slotted subject: corner brackets draw on, label:value lines tick their values on cues, one readout emphasized in accent. The subject never moves; the HUD breathes zero.",
+  "tags": ["motion-primitive", "product-demo", "hud", "telemetry", "deterministic"],
+  "jobs": ["demonstrate"],
+  "family": "product-demo",
+  "profile": "holdable",
+  "evidence": "Wave K K4 telemetry-hud specification; text-at-time value ticking generalized from typed-prompt, bracket draw from the marker-highlight dash law with attribute-driven dashoffset",
+  "syncPoints": [{ "id": "readouts-settled", "phase": "in", "offset": 2.35 }],
+  "files": [
+    {
+      "path": "telemetry-hud.html",
+      "target": "compositions/components/telemetry-hud.html",
+      "type": "hyperframes:snippet"
+    }
+  ],
+  "variables": [
+    {
+      "id": "readouts",
+      "type": "string",
+      "role": "content",
+      "label": "Readouts",
+      "description": "Comma-separated label:value pairs, up to 8. The first colon splits label from value.",
+      "default": "fps:59.94,latency:11.8 ms,gpu:38%,heap:1.2 GB"
+    },
+    {
+      "id": "emphasize",
+      "type": "number",
+      "role": "style",
+      "label": "Emphasize",
+      "description": "Index of the readout rendered in the accent color. -1 disables.",
+      "default": 0,
+      "min": -1,
+      "max": 7,
+      "step": 1
+    },
+    {
+      "id": "cues",
+      "type": "string",
+      "role": "timing",
+      "label": "Cues",
+      "description": "Comma-separated seconds relative to mount start; cue N starts readout N value tick. Empty uses the authored rhythm.",
+      "default": ""
+    },
+    {
+      "id": "accent",
+      "type": "enum",
+      "role": "style",
+      "label": "Accent",
+      "description": "Color of the emphasized readout.",
+      "default": "green",
+      "options": [
+        { "value": "green", "label": "Green" },
+        { "value": "blue", "label": "Blue" },
+        { "value": "violet", "label": "Violet" }
+      ]
+    },
+    {
+      "id": "exit",
+      "type": "enum",
+      "role": "timing",
+      "label": "Exit",
+      "description": "Outgoing transition. Frame roots own transitions; none holds the end frame.",
+      "default": "none",
+      "options": [
+        { "value": "none", "label": "None" },
+        { "value": "fade", "label": "Fade" },
+        { "value": "up", "label": "Up" }
+      ]
+    }
+  ]
+}