feat: add help command

lnbits/extensions/watchonly/static/js/index.js

@@ -840,6 +840,23 @@ new Vue({
         })
       }
     },
+    hwwHelp: async function () {
+      try {
+        await this.serial.writer.write(COMMAND_HELP + '\n')
+        this.$q.notify({
+          type: 'positive',
+          message: 'Check display or console for details!',
+          timeout: 5000
+        })
+      } catch (error) {
+        this.$q.notify({
+          type: 'warning',
+          message: 'Failed to ask for help!',
+          caption: `${error}`,
+          timeout: 10000
+        })
+      }
+    },
     //################### UTXOs ###################
     scanAllAddresses: async function () {
       await this.refreshAddresses()

lnbits/extensions/watchonly/static/js/utils.js

@@ -3,6 +3,7 @@ const COMMAND_PASSWORD = '/password'
 const COMMAND_PASSWORD_CLEAR = '/password-clear'
 const COMMAND_SEND_PSBT = '/psbt'
 const COMMAND_SIGN_PSBT = '/sign'
+const COMMAND_HELP = '/help'
 
 const blockTimeToDate = blockTime =>
   blockTime ? moment(blockTime * 1000).format('LLL') : ''