drained: add ability to disable other boot code

apps/drained/boot.ts

@@ -1,7 +1,16 @@
-const { battery = 5, interval = 10 }: DrainedSettings = require("Storage")
-  .readJSON(`${app}.setting.json`, true) || {};
+const { battery = 5, interval = 10, disableBoot = false }: DrainedSettings
+  = require("Storage").readJSON(`drained.setting.json`, true) || {};
 
-let drainedInterval: number | undefined = setInterval(() => {
+if(disableBoot){
+  require("Storage").erase(".boot0");
+
+  Bangle.on("charging", charging => {
+    if (charging)
+      eval(require('Storage').read('bootupdate.js'));
+  });
+}
+
+drainedInterval = setInterval(() => {
   if(Bangle.isCharging())
     return;
   if(E.getBattery() > battery)

apps/drained/settings.ts

@@ -1,6 +1,7 @@
 type DrainedSettings = {
   battery?: number,
   interval?: number,
+  disableBoot?: ShortBoolean,
 };
 
 ((back: () => void) => {
@@ -10,6 +11,7 @@ type DrainedSettings = {
   const settings: DrainedSettings = storage.readJSON(SETTINGS_FILE, true) || {};
   settings.battery ??= 5;
   settings.interval ??= 10;
+  settings.disableBoot ??= false;
 
   const save = () => {
     storage.writeJSON(SETTINGS_FILE, settings)
@@ -18,6 +20,14 @@ type DrainedSettings = {
   E.showMenu({
     "": { "title": "Drained" },
     "< Back": back,
+    "Keep startup code": {
+      value: settings.disableBoot,
+      format: () => settings.disableBoot ? "No" : "Yes",
+      onchange: () => {
+        settings.disableBoot = !settings.disableBoot;
+        save();
+      },
+    },
     "Trigger at batt%": {
       value: settings.battery,
       min: 0,