One firmware: the Debug Console in every build, off until switched on, with the device's own token

There is no Debug Build any more (ADR 0010, issue #68, Q188 to Q195). The
console and the test commands are compiled into every firmware. It listens
only while Settings > Debug Console is on, which isn't the default; off,
neither its task nor its 4 KB ring exists. The token is made by the device
and shown on that page; a client proves it knows it by answering a challenge
with an HMAC, so it never crosses the network, and five wrong answers close
the console for a minute. DBG in the Status Bar while it listens.

Over USB serial only: debug on, debug token <value>, debug token new.
scripts/flash.sh --debug uses them to set a device up with the developer's
token. scripts/rdbg.py takes the token from -t, $RORO_DEBUG_TOKEN or the
file, answers the challenge, and fetches a release's ELF to decode a crash.

Gone: the cardputer-adv-debug environment, RORO_DEBUG, the +debug version,
scripts/debug_flags.py, update install ... force, and the rule that a Debug
Build doesn't install releases. Old clients and old firmwares don't talk to
each other.

Against the builds it replaces: 30 KB more flash and 88 bytes more static
RAM than the release, 4 KB less RAM than the Debug Build. 468 host tests.
Checked on the device: off by default, login, the pause after wrong tokens,
Safe Mode with the console, the setting surviving an update, debug off.

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

src/apps/settings_app.h

@@ -13,6 +13,7 @@
 #include "services/battery_service.h"
 #include "services/clock_service.h"
 #include "services/storage_service.h"
+#include "apps/debug_console_page.h"
 #include "apps/firmware_page.h"
 #include "apps/wifi_settings_page.h"
 #include "settings_menu.h"
@@ -32,24 +33,26 @@ struct SettingsAppDeps {
     UpdateService& update;
 };
 
-// Settings: every user-facing setting, plus the Wi-Fi, Firmware and About pages.
+// Settings: every user-facing setting, plus the Wi-Fi, Firmware, Debug Console and About pages.
 class SettingsApp : public App {
    public:
     explicit SettingsApp(const SettingsAppDeps& deps)
         : d_(deps),
           menu_(deps.settings),
           wifiPage_(deps.settings, deps.savedNetworks, deps.wifi, deps.bus),
-          firmwarePage_(deps.update, deps.wifi, deps.storage) {}
+          firmwarePage_(deps.update, deps.wifi, deps.storage),
+          debugPage_(deps.settings, deps.wifi) {}
     void onEnter() override;
     bool onKey(const KeyEvent& e) override;
     void update(uint32_t nowMs) override;
     bool textEntryActive() const override {
-        return page_ == Page::Text || (page_ == Page::Wifi && wifiPage_.textEntryActive());
+        return page_ == Page::Text || (page_ == Page::Wifi && wifiPage_.textEntryActive()) ||
+               (page_ == Page::Debug && debugPage_.textEntryActive());
     }
     void draw(Canvas& c) override;
 
    private:
-    enum class Page { Menu, Text, Choice, About, Wifi, Firmware };
+    enum class Page { Menu, Text, Choice, About, Wifi, Firmware, Debug };
 
     bool onMenuKey(const KeyEvent& e);
     bool onTextKey(const KeyEvent& e);
@@ -62,6 +65,7 @@ class SettingsApp : public App {
     SettingsMenu menu_;
     WifiSettingsPage wifiPage_;
     FirmwarePage firmwarePage_;
+    DebugConsolePage debugPage_;
     Page page_ = Page::Menu;
     ListModel list_{theme::kContent.h / theme::kLineHeight};
     ListModel choices_{theme::kContent.h / theme::kLineHeight};