Initial commit: Revids REST API for LTX-2.3 image-to-video generation

- FastAPI with job polling: POST /generate, GET /jobs/{id}, /download, /health
- SQLite job persistence (aiosqlite), background task processing
- LTX-2.3 DistilledPipeline via native ltx-pipelines (editable install from submodule)
- Configurable model paths, LoRA support, FP8 quantization via env vars
- Single-concurrency GPU lock for safe inference
- LTX-2 as git submodule under libs/

app/models.py

@@ -0,0 +1,43 @@
+from __future__ import annotations
+
+import uuid
+from typing import Optional
+
+from pydantic import BaseModel, Field
+
+
+# --- Request ---
+
+class GenerateRequest(BaseModel):
+    prompt: Optional[str] = Field(None, description="Optional text prompt to guide generation")
+    width: int = Field(768, ge=256, le=2048, multiple_of=32, description="Video width (must be divisible by 32)")
+    height: int = Field(512, ge=256, le=2048, multiple_of=32, description="Video height (must be divisible by 32)")
+    num_frames: int = Field(65, ge=9, le=257, description="Frame count (must be 8n+1)")
+    fps: float = Field(24.0, gt=0, le=60, description="Frames per second")
+    seed: Optional[int] = Field(None, description="Random seed for reproducibility")
+
+
+# --- Job Status ---
+
+class JobStatusResponse(BaseModel):
+    job_id: str
+    status: str  # pending, processing, completed, failed
+    prompt: Optional[str] = None
+    params: Optional[dict] = None
+    error: Optional[str] = None
+    created_at: Optional[str] = None
+    completed_at: Optional[str] = None
+
+
+# --- Submission Response ---
+
+class JobSubmitResponse(BaseModel):
+    job_id: str
+    status: str = "pending"
+    message: str = "Job submitted. Poll GET /jobs/{job_id} for status."
+
+
+# --- Error ---
+
+class ErrorResponse(BaseModel):
+    error: str