feat: add common aspect ratios to image outpaint

[miaomiaozii]

Summary

• add common outpaint ratio presets to both classic and smart canvas flows
• share ratio calculation logic across the two interfaces
• refresh canvas and i18n static asset versions to avoid stale frontend files

Verification

• 3 focused ratio tests passed
• relevant JavaScript syntax checks passed

For providers with a restricted native ratio list, request compatibility is handled by the model-routing change in the separate PR.