feat(video): native Google Veo + xAI Grok Imagine async video providers (#278) (#282)

Closes #278.

Adds first-class aimock support for two async video-generation
providers, mirroring the existing Sora / OpenRouter / fal job-lifecycle
model — replay **and** live record-mode proxy for both.

## Google Veo (Gemini)
- `POST /v1beta/models/{model}:predictLongRunning` → `{ name }`, then
`GET /v1beta/operations/{name}` poll → `{ done:false }` … `{ done:true,
response.generateVideoResponse.generatedSamples[].video.uri }`, with
poll-count progression.
- Files-API `uri` is served as-is (aimock does not proxy the video bytes
— Veo's envelope carries no cost field).
- Record mode forwards 1:1 to the configured `veo` upstream and
eager-captures the fixture on `done:true`.

## xAI Grok Imagine
- `POST /v1/videos/generations` → `{ request_id }` (multipart rejected
with 400), then `GET /v1/videos/{request_id}` → `{ status:
pending|done|failed|expired, progress, video, usage.cost_in_usd_ticks
}`. Progress synthesized from poll count; `cost_in_usd_ticks` = USD ×
1e10.
- Shares `/v1/videos/{id}` with Sora: job-map-first lookup, falling
through to the **unchanged** Sora handler on a miss (pinned
byte-for-byte by a test).
- Record mode forwards 1:1 to the configured `grok` upstream and
eager-captures on terminal status.

Shared proxy helpers were extracted into `src/video-proxy-shared.ts`
(behavior-preserving; openrouter-video re-pointed at it, its 233 tests
green before & after).

## Verification
- Full suite **4113 passing** (127 files), build + exports + lint +
format + `tsc --noEmit` all clean.
- Both providers have red-green-proven replay + record tests against a
credential-free fake local upstream (no real Veo/xAI keys needed).
- Reviewed via a 4-round, 9-agent-per-round CR loop converged to zero
(Procedure 3 bucket-c audit: 0 promotions). Behavioral fixes
(failed-seed progress, status-dispatch error journaling for both
providers, empty-url placeholder) each landed with a red→green covering
test.

## Known follow-ups (not blocking)
- **Verify** `@google/genai` forwards `x-test-id` on
`operations.getVideosOperation` polls; if it does not, Veo would need
testId conveyance via the operation name (like OpenRouter's
`testIdSuffix`) for non-default-testId clients. Consistent with Sora's
contract today.
- Minor hardening logged: guard Grok's poll-URL build like Veo's;
reconcile the capture-latch reset discipline across the two;
`Number.isFinite` guards + warns on malformed upstream duration/cost.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Author: jpr5

CHANGELOG.md

@@ -2,6 +2,13 @@
 
 ## [Unreleased]
 
+### Added
+
+- Native Google Veo async video lifecycle mock — `POST /v1beta/models/{model}:predictLongRunning` submit, `GET /v1beta/operations/{name}` poll through `done:false → done:true`, poll-count progression via `veoVideo`; the Files-API `uri` is served as-is (aimock never proxies or downloads video bytes) (#278)
+- Record-mode live proxying for the Veo surface (`record.providers.veo`) — submit and poll forwarded 1:1, eager fixture capture of the Files-API uri on `done:true`; captured operations replay later (#278)
+- Native xAI Grok Imagine async video lifecycle mock — `POST /v1/videos/generations` submit (JSON-only; multipart rejected with 400), `GET /v1/videos/{request_id}` poll through `pending → done | failed | expired` with synthesized `progress`, `grokVideo` progression, `cost_in_usd_ticks` units, and a Sora-safe `/v1/videos/{id}` dispatch that leaves the OpenAI video surface unchanged (#278)
+- Record-mode live proxying for the Grok surface (`record.providers.grok`) — submit and poll forwarded 1:1, eager fixture capture of url/duration/cost on `done`, `failed` persisted, `expired` passed through; captured jobs replay later (#278)
+
 ## [1.34.0] - 2026-06-24
 
 ### Changed

README.md

@@ -52,7 +52,7 @@ Run them all on one port with `npx @copilotkit/aimock --config aimock.json`, or
 - **Timing-aware recording and replay** — Recorded fixtures capture per-frame arrival timestamps; replay uses recorded timings for approximate timing reproduction based on recorded TTFT and inter-frame cadence (replay chunk count may differ from recording — TTFT and average pace are preserved, not per-token fidelity) with configurable `--replay-speed` multiplier
 - **[Multi-turn Conversations](https://aimock.copilotkit.dev/multi-turn)** — Record and replay multi-turn traces with tool rounds; match distinct turns via `turnIndex`, `hasToolResult`, `toolCallId`, `sequenceIndex`, `systemMessage` (gate on host-supplied agent context), or custom predicates
 - **[12 providers across 14 API surfaces](https://aimock.copilotkit.dev/docs)** — OpenAI Chat, OpenAI Responses, OpenAI Realtime (GA + Beta shim), Claude, Gemini (REST + embedContent), Gemini Live, Gemini Interactions, Azure, Bedrock, Vertex AI, Ollama (chat + embeddings), Cohere (chat + embed), ElevenLabs TTS — full streaming support
-- **Multimedia APIs** — [image generation](https://aimock.copilotkit.dev/images) (DALL-E, Imagen), [image editing](https://aimock.copilotkit.dev/images) (/v1/images/edits), [text-to-speech](https://aimock.copilotkit.dev/speech) (OpenAI + ElevenLabs), [audio transcription](https://aimock.copilotkit.dev/transcription), [audio translation](https://aimock.copilotkit.dev/transcription) (/v1/audio/translations), [video generation](https://aimock.copilotkit.dev/video), [OpenRouter video generation](https://aimock.copilotkit.dev/openrouter-video) (/api/v1/videos with async job lifecycle), [fal.ai](https://aimock.copilotkit.dev/fal-ai) (image / video / audio with queue lifecycle)
+- **Multimedia APIs** — [image generation](https://aimock.copilotkit.dev/images) (DALL-E, Imagen), [image editing](https://aimock.copilotkit.dev/images) (/v1/images/edits), [text-to-speech](https://aimock.copilotkit.dev/speech) (OpenAI + ElevenLabs), [audio transcription](https://aimock.copilotkit.dev/transcription), [audio translation](https://aimock.copilotkit.dev/transcription) (/v1/audio/translations), [video generation](https://aimock.copilotkit.dev/video), [OpenRouter video generation](https://aimock.copilotkit.dev/openrouter-video) (/api/v1/videos with async job lifecycle), [Google Veo video generation](https://aimock.copilotkit.dev/veo-video) (:predictLongRunning + /v1beta/operations async lifecycle), [Grok Imagine video generation](https://aimock.copilotkit.dev/grok-video) (/v1/videos/generations with async job lifecycle), [fal.ai](https://aimock.copilotkit.dev/fal-ai) (image / video / audio with queue lifecycle)
 - **[MCP](https://aimock.copilotkit.dev/mcp-mock) / [A2A](https://aimock.copilotkit.dev/a2a-mock) / [AG-UI](https://aimock.copilotkit.dev/agui-mock) / [Vector](https://aimock.copilotkit.dev/vector-mock)** — Mock every protocol your AI agents use
 - **[Chaos Testing](https://aimock.copilotkit.dev/chaos-testing)** — 500 errors, malformed JSON, mid-stream disconnects at any probability
 - **Per-Request Strict Mode** — `X-AIMock-Strict` header overrides the server-level `--strict` flag per request (`true`/`1` = strict, `false`/`0` = lenient)

docs/grok-video/index.html

@@ -37,6 +37,8 @@
         { label: "Audio Transcription", href: "/transcription" },
         { label: "Video Generation", href: "/video" },
         { label: "OpenRouter Video", href: "/openrouter-video" },
+        { label: "Google Veo Video", href: "/veo-video" },
+        { label: "Grok Imagine Video", href: "/grok-video" },
         { label: "fal.ai", href: "/fal-ai" },
       ],
     },