Fix auth, database issues, add provider API endpoint

- Fixed bcrypt password hashing compatibility
- Fixed cookie-based authentication persistence
- Added withCredentials for cookie support
- Fixed Nano Banana logger error
- Fixed Imagen to use REST API instead of Vertex AI
- Fixed Topaz hydration errors
- Added Flux API key
- Fixed database corruption from disk space
- Added thumbnail_path column
- Added provider capabilities API endpoint
- Added voice library save/load functionality
- Enhanced text-to-speech with more voice settings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 (1M context) <noreply@anthropic.com>

backend/app/api/v1/modules.py

@@ -617,6 +617,19 @@ async def generate_alt_text(
     return job_response(job)
 
 
+@router.get("/image/providers")
+def get_image_providers():
+    """Get all image providers with their capabilities"""
+    from app.services.image_generator import IMAGE_PROVIDERS, STABILITY_STYLE_PRESETS
+
+    # Add Stability style presets to the config
+    providers = IMAGE_PROVIDERS.copy()
+    if "stable-diffusion" in providers:
+        providers["stable-diffusion"]["style_presets"] = STABILITY_STYLE_PRESETS
+
+    return providers
+
+
 @router.post("/text/enhance-prompt")
 async def enhance_prompt(
     request: PromptEnhanceRequest,