chore: merge upstream v12.4.7 + keep local fixes

Major upstream changes (v12.3.9 → v12.4.7):

v12.3.9 — Stop hook fire-and-forget (eliminates ~110s terminal block);
  hook port precedence; Telegram notifier; security_alert/security_note
  observation types

v12.4.0/12.4.1 — worker startup streamlined; consolidated DB connections;
  Chroma backfill watermark cache (422% CPU → 0% on restart)

v12.4.2 — context-overflow infinite loop fixed (clears memorySessionId
  on "Prompt is too long"); <task-notification> payload pollution blocked
  at hook + worker boundary

v12.4.3 — one-time pollution cleanup migration (CleanupV12_4_3):
  purges observer-sessions rows + cascade, stuck pending chains, Chroma
  rebuild; auto VACUUM INTO backup. Ran successfully on this DB:
  - 1463 observer-sessions purged
  - 3682 cascade rows
  - 102MB backup at ~/.claude-mem/backups/

v12.4.4 — stop draining queue on /clear (removes SessionEnd shim that
  had been abandoning pending observations for 6 months)

v12.4.5 — fix observation persistence on fresh installs (migration 28
  mirror in SessionStore)

v12.4.7 — cynical-deletion sweep (closes 27 issues); multi-account
  isolation via per-UID worker port (37700 + uid % 100, with explicit
  CLAUDE_MEM_WORKER_PORT override); CLAUDE_MEM_INTERNAL=1 trust boundary
  replaces cwd-based observer-session detection; observations.metadata
  column (migration 30); proxy env vars stripped from spawned subprocs

Local fixes preserved:
- env-sanitizer PATH extension for claude CLI lookup (auto-merged
  cleanly with upstream's new ENV_PROXY_VARS proxy stripping)
- SessionStore stale session reset (mac sleep / 4h wall-clock)

Settings: CLAUDE_MEM_WORKER_PORT=37777 explicit override preserved
through the per-UID port migration. Worker restarted to v12.4.7.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugin/scripts/smart-install.js

@@ -339,61 +339,6 @@ function installUv() {
   }
 }
 
-/**
- * Add shell alias for claude-mem command
- */
-function installCLI() {
-  const WORKER_CLI = join(ROOT, 'scripts', 'worker-service.cjs');
-  const bunPath = getBunPath() || 'bun';
-  const aliasLine = `alias claude-mem='${bunPath} "${WORKER_CLI}"'`;
-  const markerPath = join(ROOT, '.cli-installed');
-
-  // Skip if already installed
-  if (existsSync(markerPath)) return;
-
-  try {
-    if (IS_WINDOWS) {
-      // Windows: Add to PATH via PowerShell profile
-      const profilePath = join(process.env.USERPROFILE || homedir(), 'Documents', 'PowerShell', 'Microsoft.PowerShell_profile.ps1');
-      const profileDir = join(process.env.USERPROFILE || homedir(), 'Documents', 'PowerShell');
-      const functionDef = `function claude-mem { & "${bunPath}" "${WORKER_CLI}" $args }\n`;
-
-      if (!existsSync(profileDir)) {
-        execSync(`mkdir "${profileDir}"`, { stdio: 'ignore', shell: true });
-      }
-
-      const existingContent = existsSync(profilePath) ? readFileSync(profilePath, 'utf-8') : '';
-      if (!existingContent.includes('function claude-mem')) {
-        writeFileSync(profilePath, existingContent + '\n' + functionDef);
-        console.error(`✅ PowerShell function added to profile`);
-        console.error('   Restart your terminal to use: claude-mem <command>');
-      }
-    } else {
-      // Unix: Add alias to shell configs
-      const shellConfigs = [
-        join(homedir(), '.bashrc'),
-        join(homedir(), '.zshrc')
-      ];
-
-      for (const config of shellConfigs) {
-        if (existsSync(config)) {
-          const content = readFileSync(config, 'utf-8');
-          if (!content.includes('alias claude-mem=')) {
-            writeFileSync(config, content + '\n' + aliasLine + '\n');
-            console.error(`✅ Alias added to ${config}`);
-          }
-        }
-      }
-      console.error('   Restart your terminal to use: claude-mem <command>');
-    }
-
-    writeFileSync(markerPath, new Date().toISOString());
-  } catch (error) {
-    console.error(`⚠️  Could not add shell alias: ${error.message}`);
-    console.error(`   Use directly: ${bunPath} "${WORKER_CLI}" <command>`);
-  }
-}
-
 /**
  * Check if dependencies need to be installed
  */
@@ -629,8 +574,8 @@ try {
     // Worker will be started fresh by next hook in chain (worker-service.cjs start)
   }
 
-  // Step 4: Install CLI to PATH
-  installCLI();
+  // Step 4 (removed in #2054): legacy `claude-mem` shell alias was deleted.
+  // Users invoke the CLI via `npx claude-mem <cmd>` or `bunx claude-mem <cmd>`.
 
   // Step 5: Warn if the bundled native binary is incompatible with this platform
   checkBinaryPlatformCompatibility();