The Electron desktop app writes boot failures, backend spawn output, and
Python tracebacks to HERMES_HOME/logs/desktop.log, but debug-share only
captured agent/errors/gateway — so desktop boot issues never made it into
shared debug reports.
- logs.py: register desktop -> desktop.log (enables 'hermes logs desktop')
- debug.py: capture desktop snapshot, add to summary report, upload full
desktop.log in 'share', update privacy notice
- gateway /debug inherits the desktop tail via collect_debug_report()
- main.py + docs: help text and log-name table (also adds missing gui row)
- tests: desktop seed in fixture, new report test, three_pastes -> four_pastes