[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_lucy_edit.py

@@ -1,18 +1,27 @@
 from fastvideo import VideoGenerator
+from fastvideo.api import (
+    EngineConfig, GenerationRequest, GeneratorConfig, InputConfig,
+    OffloadConfig, OutputConfig, SamplingConfig,
+)
 
 OUTPUT_PATH = "video_samples_lucy_edit"
 
 
 def main():
-    generator = VideoGenerator.from_pretrained(
-        "decart-ai/Lucy-Edit-Dev",
-        num_gpus=1,
-        use_fsdp_inference=False,
-        dit_cpu_offload=True,
-        vae_cpu_offload=False,
-        text_encoder_cpu_offload=True,
-        pin_cpu_memory=True,
-    )
+    generator = VideoGenerator.from_config(
+        GeneratorConfig(
+            model_path="decart-ai/Lucy-Edit-Dev",
+            engine=EngineConfig(
+                num_gpus=1,
+                use_fsdp_inference=False,
+                offload=OffloadConfig(
+                    dit=True,
+                    vae=False,
+                    text_encoder=True,
+                    pin_cpu_memory=True,
+                ),
+            ),
+        ))
 
     prompt = ("Change the apron and blouse to a classic clown costume: satin "
               "polka-dot jumpsuit in bright primary colors, ruffled white collar, "
@@ -20,18 +29,20 @@ def main():
               "foam nose; soft window light from left, eye-level medium shot.")
     video_path = "https://d2drjpuinn46lb.cloudfront.net/painter_original_edit.mp4"
 
-    generator.generate_video(
-        prompt,
-        negative_prompt="",
-        video_path=video_path,
-        output_path=OUTPUT_PATH,
-        save_video=True,
-        height=480,
-        width=832,
-        num_frames=81,
-        fps=24,
-        guidance_scale=5.0,
-    )
+    generator.generate(
+        GenerationRequest(
+            prompt=prompt,
+            negative_prompt="",
+            inputs=InputConfig(video_path=video_path),
+            sampling=SamplingConfig(
+                height=480,
+                width=832,
+                num_frames=81,
+                fps=24,
+                guidance_scale=5.0,
+            ),
+            output=OutputConfig(output_path=OUTPUT_PATH, save_video=True),
+        ))
 
 
 if __name__ == "__main__":