[ARCH-D-2.8] Remove ZHTP Router Bypass Paths

[umwelt]

Phase: 2 - P1-High
Category: ZHTP Layer Cleanup
Files: zhtp/src/server/bluetooth/router.rs, wifi/router.rs, quic/handler.rs
Depends on: Ticket 2.5

Description

All messages must go through MeshRouter (currently 3 bypass paths)

Current Problem

• bluetooth/router.rs:150-180 bypasses router
• wifi/router.rs bypasses router
• quic/handler.rs bypasses router

Key Tasks

• Refactor BLE → mesh_router.route_message()
• Refactor WiFi → mesh_router.route_message()
• Refactor QUIC → mesh_router.route_message()
• Remove direct protocol calls

Acceptance Criteria

• All messages logged by router
• No bypass paths remain

References

See ARCHITECTURAL_FIXES_IMPLEMENTATION_PLAN.md Ticket 2.8