P1 first slice of the voice pipeline migration (spec
docs/superpowers/specs/2026-05-03-voice-pipeline-esp-sr-design.md).
Adds idf_zacus/ alongside the Arduino tree (ui_freenove_allinone/
keeps building unchanged). The scaffold targets ESP32-S3, octal
PSRAM 80 MHz, custom partition table with OTA + 2 MB LittleFS.
main/main.c boots, initializes NVS, mounts LittleFS on /littlefs,
logs heap stats (internal + PSRAM), and idles with a 60 s
heartbeat. The orphaned 2026-04-03 ota_server component
(HTTP :80, rate-limited OTA upload, 30 s rollback watchdog) is
folded in under components/ota_server/ and its header is fixed
to include esp_http_server.h (matches the .c, port 80 = HTTP).
Not yet wired: ota_server_init() boot, Wi-Fi STA, voice/NPC
modules. Stubs for puzzle_get_battery_pct() and
puzzle_get_espnow_peer_count() let the OTA component link.