Reorganize API plus anim notebook improvements

[pharmapsychotic]

• client.Api -> api.Context
• move UI code out of animation_gradio.ipynb into animation_ui.py
• API to query user credits + PFP and display in animation UI
• new models, OutOfCreditsException, and Update last video button

[sonarcloud[bot]]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
1 Security Hotspot
20 Code Smells

No Coverage information
1.4% Duplication