New main/plip_virtual.{h,c}: implements the PLIP REST contract on the
existing port-80 httpd (POST /ring {duration_ms} with French cadence
1.5s/3.5s 440 Hz on the speaker, POST /stop, GET /status, POST /play
501 — audio flows through the WS TTS path). The BOOT button becomes
the virtual hook switch when ringing/off-hook (falls back to the
streaming toggle otherwise) and every transition is reported to the
master POST <ZACUS_MASTER_URL>/voice/hook {state,reason}, the exact
zacus_hook_client contract — the master cannot tell the annexes apart.
New Kconfig ZACUS_MASTER_URL (default 10.2.5.42). scenario_server
exposes its httpd handle for co-registration.
Build green (zacus-box3-voice.bin).
Claude Worker claude2