setup: add back-to-channels exit at every Teams step gate

Teams setup is 6+ Azure steps over 30+ minutes. Today, every
"Done / Stuck / Show again" gate forces continuation; the only escape
is Ctrl-C, which kills setup entirely. Add a fourth option at each gate
that returns to the channel picker so a stuck operator can pick a
different channel without losing the rest of setup.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

setup/channels/teams.ts

@@ -95,12 +95,25 @@ export async function runTeamsChannel(_displayName: string): Promise<ChannelFlow
   const prereqsResult = await confirmPrereqs({ collected, completed });
   if (prereqsResult === 'back') return BACK_TO_CHANNEL_SELECTION;
   await stepPublicUrl({ collected, completed });
-  await stepAppRegistration({ collected, completed });
+  if (await stepAppRegistration({ collected, completed }) === 'back') {
-  await stepClientSecret({ collected, completed });
+    return BACK_TO_CHANNEL_SELECTION;
-  await stepAzureBot({ collected, completed });
+  }
-  await stepEnableTeamsChannel({ collected, completed });
+  if (await stepClientSecret({ collected, completed }) === 'back') {
+    return BACK_TO_CHANNEL_SELECTION;
+  }
+  if (await stepAzureBot({ collected, completed }) === 'back') {
+    return BACK_TO_CHANNEL_SELECTION;
+  }
+  if (await stepEnableTeamsChannel({ collected, completed }) === 'back') {
+    return BACK_TO_CHANNEL_SELECTION;
+  }
   const manifestResult = await stepGenerateManifest({ collected, completed });
-  await stepSideload({ collected, completed, zipPath: manifestResult.zipPath });
+  if (
+    await stepSideload({ collected, completed, zipPath: manifestResult.zipPath })
+    === 'back'
+  ) {
+    return BACK_TO_CHANNEL_SELECTION;
+  }
 
   await installAdapter(collected);
   completed.push('Adapter installed and service restarted.');
@@ -229,7 +242,7 @@ async function stepPublicUrl(args: { collected: Collected; completed: string[] }
 async function stepAppRegistration(args: {
   collected: Collected;
   completed: string[];
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   note(
     [
       `1. In ${AZURE_PORTAL_URL}, search "App registrations" → "New registration"`,
@@ -262,15 +275,17 @@ async function stepAppRegistration(args: {
     );
   }
 
-  await stepGate({
+  const gate = await stepGate({
     stepName: 'teams-app-registration',
     stepDescription: 'registering an app in Azure and collecting App ID + tenant type',
     reshow: () => stepAppRegistration(args),
     args,
   });
+  if (gate === 'back') return 'back';
   args.completed.push(
     `App registered: ${args.collected.appId} (${args.collected.appType})`,
   );
+  return 'continue';
 }
 
 async function askAppType(args: {
@@ -313,7 +328,7 @@ async function askAppType(args: {
 async function stepClientSecret(args: {
   collected: Collected;
   completed: string[];
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   note(
     [
       `1. In your app registration, open "Certificates & secrets"`,
@@ -356,13 +371,15 @@ async function stepClientSecret(args: {
     break;
   }
 
-  await stepGate({
+  const gate = await stepGate({
     stepName: 'teams-client-secret',
     stepDescription: 'creating and copying the client secret',
     reshow: () => stepClientSecret(args),
     args,
   });
+  if (gate === 'back') return 'back';
   args.completed.push('Client secret captured.');
+  return 'continue';
 }
 
 // ─── step: Azure Bot resource ──────────────────────────────────────────
@@ -370,7 +387,7 @@ async function stepClientSecret(args: {
 async function stepAzureBot(args: {
   collected: Collected;
   completed: string[];
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   const endpoint = `${args.collected.publicUrl}/api/webhooks/teams`;
   const tenantFlag =
     args.collected.appType === 'SingleTenant'
@@ -405,14 +422,16 @@ async function stepAzureBot(args: {
     'Step 3 of 6 — Create Azure Bot resource',
   );
 
-  await stepGate({
+  const gate = await stepGate({
     stepName: 'teams-azure-bot',
     stepDescription:
       'creating an Azure Bot resource linked to the app registration and setting the messaging endpoint',
     reshow: () => stepAzureBot(args),
     args,
   });
+  if (gate === 'back') return 'back';
   args.completed.push('Azure Bot created; messaging endpoint configured.');
+  return 'continue';
 }
 
 // ─── step: enable Teams channel ────────────────────────────────────────
@@ -420,7 +439,7 @@ async function stepAzureBot(args: {
 async function stepEnableTeamsChannel(args: {
   collected: Collected;
   completed: string[];
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   note(
     [
       '1. Open your Azure Bot resource → Channels',
@@ -431,13 +450,15 @@ async function stepEnableTeamsChannel(args: {
     ].join('\n'),
     'Step 4 of 6 — Enable Teams channel on the bot',
   );
-  await stepGate({
+  const gate = await stepGate({
     stepName: 'teams-enable-channel',
     stepDescription: 'enabling the Microsoft Teams channel on the Azure Bot resource',
     reshow: () => stepEnableTeamsChannel(args),
     args,
   });
+  if (gate === 'back') return 'back';
   args.completed.push('Teams channel enabled on the bot.');
+  return 'continue';
 }
 
 // ─── step: manifest zip ────────────────────────────────────────────────
@@ -490,7 +511,7 @@ async function stepSideload(args: {
   collected: Collected;
   completed: string[];
   zipPath: string;
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   note(
     [
       '1. Open Microsoft Teams',
@@ -505,13 +526,15 @@ async function stepSideload(args: {
     ].join('\n'),
     'Step 5 of 6 — Sideload the app into Teams',
   );
-  await stepGate({
+  const gate = await stepGate({
     stepName: 'teams-sideload',
     stepDescription: 'uploading the generated zip into Teams as a custom app',
-    reshow: () => stepSideload(args),
+    reshow: () => stepSideload({ ...args, zipPath: args.zipPath }),
     args,
   });
+  if (gate === 'back') return 'back';
   args.completed.push('App sideloaded into Teams.');
+  return 'continue';
 }
 
 // ─── step: install adapter ─────────────────────────────────────────────
@@ -623,9 +646,9 @@ async function finishWithHandoff(
 async function stepGate(args: {
   stepName: string;
   stepDescription: string;
-  reshow: () => Promise<void> | Promise<unknown>;
+  reshow: () => Promise<'continue' | 'back'>;
   args: { collected: Collected; completed: string[] };
-}): Promise<void> {
+}): Promise<'continue' | 'back'> {
   while (true) {
     const choice = ensureAnswer(
       await brightSelect({
@@ -634,10 +657,12 @@ async function stepGate(args: {
           { value: 'done', label: "Done — let's continue" },
           { value: 'help', label: 'Stuck — hand me off to Claude' },
           { value: 'reshow', label: 'Show me the steps again' },
+          { value: 'back', label: '← Back to channel selection' },
         ],
       }),
     );
-    if (choice === 'done') return;
+    if (choice === 'done') return 'continue';
+    if (choice === 'back') return 'back';
     if (choice === 'help') {
       await offerHandoff({
         step: args.stepName,
@@ -647,8 +672,7 @@ async function stepGate(args: {
       continue;
     }
     if (choice === 'reshow') {
-      await args.reshow();
+      return args.reshow();
-      return;
     }
   }
 }