fix(auto-update): revert config pin on install failure to prevent version mismatch

When bun install fails after updating the config pin, the config now shows the
new version but the actual package is the old one. Add revertPinnedVersion() to
roll back the config entry on install failure, keeping config and installed
version in sync.

Ref #1472

src/hooks/auto-update-checker/checker/pinned-version-updater.ts

@@ -2,10 +2,9 @@ import * as fs from "node:fs"
 import { log } from "../../../shared/logger"
 import { PACKAGE_NAME } from "../constants"
 
-export function updatePinnedVersion(configPath: string, oldEntry: string, newVersion: string): boolean {
+function replacePluginEntry(configPath: string, oldEntry: string, newEntry: string): boolean {
   try {
     const content = fs.readFileSync(configPath, "utf-8")
-    const newEntry = `${PACKAGE_NAME}@${newVersion}`
 
     const pluginMatch = content.match(/"plugin"\s*:\s*\[/)
     if (!pluginMatch || pluginMatch.index === undefined) {
@@ -51,3 +50,13 @@ export function updatePinnedVersion(configPath: string, oldEntry: string, newVer
     return false
   }
 }
+
+export function updatePinnedVersion(configPath: string, oldEntry: string, newVersion: string): boolean {
+  const newEntry = `${PACKAGE_NAME}@${newVersion}`
+  return replacePluginEntry(configPath, oldEntry, newEntry)
+}
+
+export function revertPinnedVersion(configPath: string, failedVersion: string, originalEntry: string): boolean {
+  const failedEntry = `${PACKAGE_NAME}@${failedVersion}`
+  return replacePluginEntry(configPath, failedEntry, originalEntry)
+}