docs: explain that Homebrew installs do not auto-update

Homebrew is deliberately excluded from background auto-install
(canAutoInstall), matching gh and Claude Code, but /update and the
startup notice implied auto-update exists. Both now state the brew
upgrade command and point to the native installer for automatic
background updates. ManualUpdateResult carries the install source so
the TUI can branch on it.

Author: elkaix

.changeset/homebrew-update-hint.md

@@ -0,0 +1,5 @@
+---
+'@pythoughts/pythinker-code': patch
+---
+
+Explain in `/update` and the startup update notice that Homebrew installs do not auto-update, and point to the native installer for automatic background updates.

apps/pythinker-code/src/cli/update/preflight.ts

@@ -168,11 +168,17 @@ export function renderManualUpdateMessage(
       sourceDesc = 'unsupported package manager or layout.';
       break;
   }
+  const homebrewHint =
+    source === 'homebrew'
+      ? `Homebrew installs do not auto-update. For automatic background updates, ` +
+        `switch to the native installer: ${NATIVE_INSTALL_COMMAND_UNIX}\n`
+      : '';
   return (
     `A newer version of ${NPM_PACKAGE_NAME} is available ` +
     `(${currentVersion} -> ${target.version}).\n` +
     `Detected install source: ${sourceDesc}\n` +
-    `To update manually, run: ${installCommand}\n`
+    `To update manually, run: ${installCommand}\n` +
+    homebrewHint
   );
 }
 
@@ -717,7 +723,12 @@ export type ManualUpdateResult =
   | { readonly status: 'check-failed'; readonly message: string }
   | { readonly status: 'started'; readonly version: string }
   | { readonly status: 'in-progress'; readonly version: string }
-  | { readonly status: 'manual'; readonly version: string; readonly command: string };
+  | {
+    readonly status: 'manual';
+    readonly version: string;
+    readonly command: string;
+    readonly source: InstallSource;
+  };
 
 /**
  * Explicit user-requested update (TUI `/update`). Unlike the passive
@@ -746,6 +757,7 @@ export async function startManualUpdate(
       status: 'manual',
       version: target.version,
       command: installCommandFor(source, target.version, platform),
+      source,
     };
   }
 
@@ -763,6 +775,7 @@ export async function startManualUpdate(
       status: 'manual',
       version: target.version,
       command: installCommandFor(source, target.version, platform),
+      source,
     };
   }
 

apps/pythinker-code/src/tui/commands/info.ts

@@ -10,7 +10,7 @@ import type {
 
 import { handleDoctor } from '#/cli/sub/doctor';
 import { startManualUpdate } from '#/cli/update/preflight';
-import { PYTHINKER_CODE_CHANGELOG_URL } from '#/constant/app';
+import { NATIVE_INSTALL_COMMAND_UNIX, PYTHINKER_CODE_CHANGELOG_URL } from '#/constant/app';
 import { openUrl } from '#/utils/open-url';
 import { buildMcpStatusReportLines } from '../components/messages/mcp-status-panel';
 import { buildStatusReportLines } from '../components/messages/status-panel';
@@ -323,7 +323,13 @@ export async function handleUpdateCommand(
       );
       return;
     case 'manual':
-      host.showNotice(`Update available — v${result.version}`, `Run: ${result.command}`);
+      host.showNotice(
+        `Update available — v${result.version}`,
+        result.source === 'homebrew'
+          ? `Homebrew installs do not auto-update. Run: ${result.command}\n` +
+            `For automatic background updates, switch to the native installer: ${NATIVE_INSTALL_COMMAND_UNIX}`
+          : `Run: ${result.command}`,
+      );
       return;
     case 'check-failed':
       host.showError(`Update check failed: ${result.message}`);

apps/pythinker-code/test/cli/update/preflight.test.ts

@@ -1502,6 +1502,7 @@ describe('startManualUpdate', () => {
       status: 'manual',
       version: '0.5.0',
       command: 'brew upgrade pythinker-code',
+      source: 'homebrew',
     });
     expect(mocks.spawn).not.toHaveBeenCalled();
   });