[refactor]: migrate examples/scripts to typed VideoGenerator API; rename api/compat.py to api/translation.py

Move all examples/inference and scripts off the legacy
VideoGenerator.from_pretrained(model, **kwargs) +
generate_video(prompt, **kwargs) surface onto the typed
from_config(GeneratorConfig(...)) + generate(GenerationRequest(...))
convention, including the Kandinsky-5 and DreamX-World examples added
on main after the original migration. git-mv api/compat.py to
api/translation.py ('compat' implied a temporary shim; the forward
translation is its honest permanent role) and repoint all importers,
tests, and doc links.

examples/inference/basic/basic_matrixgame3.py

@@ -1,4 +1,7 @@
 from fastvideo import VideoGenerator
+from fastvideo.api import (
+    EngineConfig, GenerationRequest, GeneratorConfig, InputConfig, OffloadConfig, OutputConfig, SamplingConfig,
+)
 
 MODEL_PATH = "FastVideo/Matrix-Game-3.0-Base-Distilled-Diffusers"
 IMAGE_URL = "https://raw.githubusercontent.com/SkyworkAI/Matrix-Game/main/Matrix-Game-3/demo_images/001/image.png"
@@ -7,28 +10,38 @@ OUTPUT_PATH = "video_samples_matrixgame3"
 
 
 def main():
-    generator = VideoGenerator.from_pretrained(
-        MODEL_PATH,
-        num_gpus=1,
-        use_fsdp_inference=False,
-        dit_cpu_offload=False,
-        vae_cpu_offload=False,
-        text_encoder_cpu_offload=True,
-        pin_cpu_memory=True,
-    )
+    generator = VideoGenerator.from_config(
+        GeneratorConfig(
+            model_path=MODEL_PATH,
+            engine=EngineConfig(
+                num_gpus=1,
+                use_fsdp_inference=False,
+                offload=OffloadConfig(
+                    dit=False,
+                    vae=False,
+                    text_encoder=True,
+                    pin_cpu_memory=True,
+                ),
+            ),
+        ))
 
-    generator.generate_video(
-        prompt=PROMPT,
-        image_path=IMAGE_URL,
-        height=720,
-        width=1280,
-        num_frames=57,
-        num_inference_steps=3,
-        guidance_scale=1.0,
-        seed=42,
-        output_path=OUTPUT_PATH,
-        save_video=True,
-    )
+    generator.generate(
+        GenerationRequest(
+            prompt=PROMPT,
+            inputs=InputConfig(image_path=IMAGE_URL),
+            sampling=SamplingConfig(
+                height=720,
+                width=1280,
+                num_frames=57,
+                num_inference_steps=3,
+                guidance_scale=1.0,
+                seed=42,
+            ),
+            output=OutputConfig(
+                output_path=OUTPUT_PATH,
+                save_video=True,
+            ),
+        ))
 
 
 if __name__ == "__main__":