Replace 11 compile-time THR_* #defines with runtime float globals
(g_thr_grass_roi, g_thr_*_collision, g_thr_*_alert) defined in
stdc_post_process.c and exposed via extern in the header.
- ini/host_stream.ini: add [detect] section with integer promille values
- kp_firmware.c: read [detect] section at startup, log initial values
- event_recorder.c: add 11 BLE SET handlers (THR_GRASS_ROI,
THR_PERSON/CAR/TREE/BUNKER/POND_COL, THR_PERSON/CAR/TREE/BUNKER/POND_ALT)
each with range validation (1-1000), runtime update, and INI persistence
- app_header_init.c: rename log field mov= to moving= for clarity