At edge tier>=2 on N16R8 PSRAM boards, `process_frame()` runs
`update_multi_person_vitals()` (4 persons × 256 history samples) plus
`wasm_runtime_on_frame()` back-to-back before returning to `edge_task()`.
The existing `vTaskDelay(1)` in `edge_task()` only fires *after*
`process_frame()` returns — under sustained 30 pps CSI load on PSRAM
boards this leaves IDLE1 on Core 1 starved long enough for the 5-second
Task Watchdog Timer to fire.
Fix: add two `vTaskDelay(1)` calls inside `process_frame()`, both gated
on `s_cfg.tier >= 2`:
1. After `update_multi_person_vitals()` (Step 11)
2. After `wasm_runtime_on_frame()` dispatch (Step 14)
Tier 0/1 paths are unaffected. Validated on COM7 (N16R8 board):
`Edge DSP task started on core 1 (tier=2)`, no WDT panics in 20 s.
Also bump firmware version 0.6.5 → 0.6.6 and refresh all 6 release_bins
with the new build (8MB + 4MB variants, built 2026-05-21).
Fix-marker RuView#683 added to scripts/fix-markers.json.
Co-Authored-By: claude-flow <ruv@ruv.net>