Safe Mode, crash reports, and a watched main loop

Every build now records at boot which version runs and, after a crash
restart, which one crashed (even across a Rollback). The core dump
summary (task, PC, reason, backtrace) is printed and raised as a
Notification; `crash` shows it later. After 3 crash restarts in a row
the firmware starts in Safe Mode: clock, Wi-Fi, Update Service and Debug
Console only (SafeMode, 2 host tests). A normal restart or a minute up
resets the count.

The main loop is now on the task watchdog (enableLoopWDT): Arduino only
watched core 0's idle task, so a stuck loop hung the device for good.
The Update Service restarts into an installed update by itself if the
main loop hasn't after 90 s.

Debug Builds: `coredump get` and `reset` are answered by the console's
own task; rdbg.py crash decodes the backtrace and rdbg.py coredump runs
esp-coredump, against ELFs archived by version and digest in .pio/elves.

The StorageService mutex is now made in the constructor: Safe Mode never
starts that Service, and `info` crashed on the null mutex, 29 times in a
row before the fix was pushed into Safe Mode over Wi-Fi.

Verified on the device: crash report and full core dump decoded over
Wi-Fi; Safe Mode at exactly 3 crashes, left by `reboot`; a hung loop
caught by the watchdog in 5 s; `reset` from the console task. ADR 0005.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

scripts/decode_coredump.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+# Full post-mortem of a core dump fetched with `scripts/rdbg.py coredump`: every task's backtrace,
+# registers and the crashed task's stack, via esp-coredump and GDB in the container.
+# Usage: scripts/decode_coredump.sh <core.bin> <version or ELF sha256 prefix>
+set -euo pipefail
+source "$(dirname "$0")/_docker.sh"
+[ $# -eq 2 ] || { echo "Usage: scripts/decode_coredump.sh <core.bin> <version|sha>" >&2; exit 1; }
+CORE="$(realpath "$1")"
+ELF="$(ls -t "$ROOT"/.pio/elves/*"$2"*.elf 2>/dev/null | head -1 || true)"
+[ -n "$ELF" ] || { echo "No archived ELF matches '$2' in .pio/elves/" >&2; exit 1; }
+echo "using ${ELF#$ROOT/}" >&2
+DOCKER_EXTRA=(-v "$(dirname "$CORE"):/core:ro")
+run_in_container /pio/penv/bin/esp-coredump --chip esp32s3 info_corefile -t raw \
+    -g /pio/tools/tool-xtensa-esp-elf-gdb/bin/xtensa-esp32s3-elf-gdb \
+    -c "/core/$(basename "$CORE")" "/work/${ELF#$ROOT/}"