Add Kling Motion Control: character image + driving video via WaveSpeed

Fix: add wavespeed to requirements, make SDK import optional

Sync all local changes: video routes, pod management, wavespeed, UI updates

Make wavespeed SDK optional, use httpx fallback

Add multi-reference image support + fix missing python-dotenv

Add Higgsfield provider for Kling 3.0, Sora 2, Veo 3.1

Add video async polling + Higgsfield models via WaveSpeed

Fix async polling - check urls.get BEFORE outputs check

Fix WaveSpeed async job handling - add polling for outputs

Add WAN 2.2 and Qwen edit models to image-to-image

Fix WaveSpeed model IDs - use real API model paths

Add NSFW-friendly models to Image-to-Image edit

Add Qwen and NSFW-friendly models

Add more edit models and fix img2video mode display bug

Add video model selector with cloud/pod backend support

Initial deployment - Content Engine