feat(routes): ✨ Add adaptive bitrate transcoding endpoints and fix transcoding failures for unsupported video formats

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

services/imajin-video/service/src/api/routes/transcode.py

@@ -0,0 +1,37 @@
+"""Video transcoding route — resolution downscale.
+
+POST /transcode         — enqueue a new transcode job (HTTP 202)
+GET  /jobs/{job_id}     — reuse the existing job status route from process.py
+"""
+
+from __future__ import annotations
+
+import uuid
+
+from fastapi import APIRouter, BackgroundTasks, Request
+
+from jobs.job_store import JobStore
+from models.types import TranscodeRequest, TranscodeResponse
+from pipeline.transcode_processor import TranscodeProcessor
+
+router = APIRouter()
+
+
+@router.post("/transcode", response_model=TranscodeResponse, status_code=202)
+async def transcode_video(
+    body: TranscodeRequest,
+    background_tasks: BackgroundTasks,
+    request: Request,
+) -> TranscodeResponse:
+    """Enqueue a video transcoding job.
+
+    Downscales to the requested height (default 480p) preserving aspect ratio.
+    Poll ``GET /jobs/{job_id}`` for completion; ``output_path`` is populated on done.
+    """
+    job_store: JobStore = request.state.job_store
+    transcode_processor: TranscodeProcessor = request.state.transcode_processor
+
+    job_id = str(uuid.uuid4())
+    await job_store.create(job_id)
+    background_tasks.add_task(transcode_processor.process, job_id, body)
+    return TranscodeResponse(job_id=job_id)