[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_self_forcing_causal.py

@@ -1,6 +1,14 @@
 import os
 import time
-from fastvideo import VideoGenerator, SamplingParam
+
+from fastvideo import VideoGenerator
+from fastvideo.api import (
+    EngineConfig,
+    GenerationRequest,
+    GeneratorConfig,
+    OffloadConfig,
+    OutputConfig,
+)
 
 OUTPUT_PATH = "video_samples_causal"
 def main():
@@ -9,23 +17,33 @@ def main():
     # If a local path is provided, FastVideo will make a best effort
     # attempt to identify the optimal arguments.
     model_name = "wlsaidhi/SFWan2.1-T2V-1.3B-Diffusers"
-    generator = VideoGenerator.from_pretrained(
-        model_name,
+    generator_config = GeneratorConfig(
+        model_path=model_name,
         # FastVideo will automatically handle distributed setup
-        num_gpus=1,
-        use_fsdp_inference=False, # set to True if GPU is out of memory
-        text_encoder_cpu_offload=False,
-        dit_cpu_offload=False,
+        engine=EngineConfig(
+            num_gpus=1,
+            use_fsdp_inference=False, # set to True if GPU is out of memory
+            offload=OffloadConfig(
+                text_encoder=False,
+                dit=False,
+            ),
+        ),
     )
-
-    sampling_param = SamplingParam.from_pretrained(model_name)
+    generator = VideoGenerator.from_config(generator_config)
 
     prompt = (
         "A curious raccoon peers through a vibrant field of yellow sunflowers, its eyes "
         "wide with interest. The playful yet serene atmosphere is complemented by soft "
         "natural light filtering through the petals. Mid-shot, warm and cheerful tones."
     )
-    video = generator.generate_video(prompt, output_path=OUTPUT_PATH, save_video=True, sampling_param=sampling_param)
+    request = GenerationRequest(
+        prompt=prompt,
+        output=OutputConfig(
+            output_path=OUTPUT_PATH,
+            save_video=True,
+        ),
+    )
+    video = generator.generate(request)
 
 if __name__ == "__main__":
     main()