docs: update analysis and add API documentation

web: Add job cancellation UI

iOS: Add job cancellation support

server: Add job cancellation endpoint

docs: update analysis.md to reflect completed items

iOS: Parse server error responses for better user feedback

server: Add Pydantic request validation and image validation

chore: enhance .gitignore and update README

docs: clear completed ToDo entries from analysis.md

docs: Mark duplicate image storage as fixed in analysis.md

iOS: Remove duplicate image storage

docs: Update analysis.md with completed tasks checked off

Refactor: Add constants, validation, and improve server code

Add history deletion.

Fix the JavaScript initialization for access to the image upload button.