feat: Auto-adapt content to platform limits when creating posts

- Add adapt_with_ai() method to PlatformAdapter that uses DeepSeek
  to condense content when it exceeds platform character limits
- Add adapt_for_all_platforms_smart() for batch adaptation
- Modify create_post endpoint to auto-generate content_x, content_threads,
  content_instagram, content_facebook with adapted versions
- Modify update_post to re-adapt content when main content changes
- If content fits within limit, use as-is (no AI call)
- If content exceeds limit, AI condenses while preserving message
- Fallback to rule-based truncation if DeepSeek API unavailable

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/api/routes/posts.py

@@ -10,6 +10,7 @@ from pydantic import BaseModel
 
 from app.core.database import get_db
 from app.models.post import Post
+from app.services.ai.platform_adapter import platform_adapter
 
 router = APIRouter()
 
@@ -122,7 +123,14 @@ async def get_post(post_id: int, db: Session = Depends(get_db)):
 
 @router.post("/", response_model=PostResponse)
 async def create_post(post_data: PostCreate, db: Session = Depends(get_db)):
-    """Crear un nuevo post."""
+    """Crear un nuevo post con auto-adaptación de contenido por plataforma."""
+
+    # Adaptar contenido para cada plataforma
+    adapted_content = await platform_adapter.adapt_for_all_platforms_smart(
+        post_data.content,
+        post_data.platforms
+    )
+
     post = Post(
         content=post_data.content,
         content_type=post_data.content_type,
@@ -131,7 +139,12 @@ async def create_post(post_data: PostCreate, db: Session = Depends(get_db)):
         image_url=post_data.image_url,
         approval_required=post_data.approval_required,
         hashtags=post_data.hashtags,
-        status="pending_approval" if post_data.approval_required else "scheduled"
+        status="pending_approval" if post_data.approval_required else "scheduled",
+        # Contenido adaptado por plataforma
+        content_x=adapted_content.get("x"),
+        content_threads=adapted_content.get("threads"),
+        content_instagram=adapted_content.get("instagram"),
+        content_facebook=adapted_content.get("facebook"),
     )
 
     db.add(post)
@@ -143,12 +156,30 @@ async def create_post(post_data: PostCreate, db: Session = Depends(get_db)):
 
 @router.put("/{post_id}")
 async def update_post(post_id: int, post_data: PostUpdate, db: Session = Depends(get_db)):
-    """Actualizar un post."""
+    """Actualizar un post con re-adaptación automática si cambia el contenido."""
     post = db.query(Post).filter(Post.id == post_id).first()
     if not post:
         raise HTTPException(status_code=404, detail="Post no encontrado")
 
     update_data = post_data.dict(exclude_unset=True)
+
+    # Si cambia el contenido principal, re-adaptar para todas las plataformas
+    if "content" in update_data:
+        platforms = update_data.get("platforms", post.platforms)
+        adapted_content = await platform_adapter.adapt_for_all_platforms_smart(
+            update_data["content"],
+            platforms
+        )
+        # Solo actualizar campos de plataforma si no vienen explícitos en la request
+        if "content_x" not in update_data and "x" in platforms:
+            update_data["content_x"] = adapted_content.get("x")
+        if "content_threads" not in update_data and "threads" in platforms:
+            update_data["content_threads"] = adapted_content.get("threads")
+        if "content_instagram" not in update_data and "instagram" in platforms:
+            update_data["content_instagram"] = adapted_content.get("instagram")
+        if "content_facebook" not in update_data and "facebook" in platforms:
+            update_data["content_facebook"] = adapted_content.get("facebook")
+
     for field, value in update_data.items():
         setattr(post, field, value)