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

lib/ota/src/safe_mode.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <cstdint>
+
+namespace roro {
+
+// Safe Mode (CONTEXT.md): after kCrashLimit starts in a row that ended in a crash, the firmware
+// starts only what it takes to be fixed over the air (Wi-Fi, Firmware Updates, the Debug Console).
+// Rollback covers new firmware; this covers firmware that was confirmed and crashes anyway.
+struct SafeMode {
+    static constexpr int kCrashLimit = 3;
+    static constexpr uint32_t kStableAfterMs = 60000;  // then the count starts over
+
+    // Called first thing at boot with the count so far; returns the new count.
+    static int countAtBoot(bool lastStartWasCrash, int crashesBefore) {
+        return lastStartWasCrash ? crashesBefore + 1 : 0;
+    }
+    static bool active(int crashes) { return crashes >= kCrashLimit; }
+};
+
+}  // namespace roro