feat(ui): more misc fixes

[psychedelicious]

• feat(ui): enable progress images by default
• fix(ui): fix edge case in nodes graph building
  Inputs with explicit values are validated by pydantic even if they also have a connection (which is the actual value that is used).
  Fix this by omitting explicit values for inputs that have a connection.
• fix(ui): fix img2img fit
• fix(ui): fix canvas bbox autoscale
• fix(ui): remove w/h from canvas params, add bbox w/h
• fix(ui): fix bug with staging bbox not resetting
  Sometimes the in-progress images would be the wrong size on canvas only.
  This was caused by the staging area not being reset when a session was canceled.
• fix(ui): set default model to first model (alpha sort)
• feat(ui): add defaultModel to config
• add tooltips to model select dropdown
• fix some incorrect parameter constraints in nodes
• some other minor fixes