feat: activate real services, fix gossip, wire sponsor backends + EventLog

fix: torch==2.11.0 for ZeroGPU compatibility (supported: 2.8-2.11)

chore: new tests, security audit, coverage enhancements, requirements update

fix: PyNaCl in requirements, file tab download+auto-refresh, impl status table

feat: mesh graph tab, routing trace, QR invite, remove all fakes, specialized-node tests

Switch Space to local-first real model backend

Add ZeroGPU startup probe

Build Phase 1 HearthNet Space