The hashcash proof-of-work implementation was incorrectly added to the
build artifact web/dist/app.js instead of the source file web/src/app.jsx.
Running web/build.sh would overwrite all hashcash changes.
Changes:
- Add checkLeadingZeros() and mintHashcash() functions to app.jsx
- Integrate hashcash into LoginScreen: fetch hashcash_bits from /server,
compute stamp via Web Crypto API before session creation, show
'Computing proof-of-work...' feedback
- Remove web/dist/ from git tracking (build artifacts)
- Add web/dist/ to .gitignore
2f905bda9f