fix: skip aspect_ratio for kling-o1 models and detect image MIME via Pillow

kling-o1-pro and kling-o1-std silently fail when aspect_ratio is included
in the payload — they derive it from the input image. Added
VIDEO_ASPECT_RATIO_MODELS whitelist so only kling-elements and minimax-hailuo
receive the parameter.

Also switched image_to_base64 to use Pillow for format detection instead of
trusting the file extension, which correctly handles files saved with the
wrong extension.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

freepik_cli/api/videos.py

@@ -9,7 +9,7 @@ from freepik_cli.api.models import (
     VIDEO_POST_ENDPOINTS,
     VIDEO_STATUS_ENDPOINTS,
     VIDEO_IMAGE_FIELDS,
-    VIDEO_SLUG_ASPECT_RATIO_MODELS,
+    VIDEO_ASPECT_RATIO_MODELS,
     VideoModel,
     get_output_urls,
     get_status,
@@ -49,7 +49,7 @@ class VideoAPI:
             effective_duration = 6
         payload["duration"] = str(effective_duration)
 
-        if aspect_ratio:
+        if aspect_ratio and model in VIDEO_ASPECT_RATIO_MODELS:
             payload["aspect_ratio"] = normalize_aspect_ratio_video(aspect_ratio, model)
 
         if seed is not None: