refactor(cli): unify daemon start error message handling

What changed:
- Added a shared utility `getErrorMessage(error: unknown)` in `packages/cli/src/utils/errors.ts`.
- Refactored `packages/cli/src/commands/daemon/start.ts` to use `getErrorMessage` and a local `exitWithError` helper instead of repeating inline error-message extraction + exit logic in each catch block.
- Added `packages/cli/tests/19-errors-utils.test.ts` to lock utility behavior for Error and non-Error throw values.

Reasoning:
- `runStart` had repeated branching (`err instanceof Error ? err.message : String(err)`) across multiple catch sites.
- Centralizing this keeps behavior stable while reducing duplication and cognitive overhead, aligned with the refactor skill guidance to simplify structure without changing user-visible behavior.

Verification:
- Ran `npx tsx packages/cli/tests/18-local-daemon-utils.test.ts` (pass).
- Ran `npx tsx packages/cli/tests/19-errors-utils.test.ts` (pass).
- Ran `npm run -w @getpaseo/cli typecheck` (pass).

Notes for next agent:
- Existing `scripts/codex-refactor-loop.sh` was already modified before this change and is intentionally not included.
- `packages/cli/tests/03-daemon.test.ts` currently failed in this environment because Test 3 expected daemon status failure, but command exited successfully (likely environment state dependent). This refactor does not touch that path; worth deflakifying or isolating in a follow-up.

packages/cli/src/commands/daemon/start.ts

@@ -12,6 +12,7 @@ import {
   startLocalDaemonDetached,
   type DaemonStartOptions as StartOptions,
 } from './local-daemon.js'
+import { getErrorMessage } from '../../utils/errors.js'
 
 export type { DaemonStartOptions as StartOptions } from './local-daemon.js'
 
@@ -73,9 +74,7 @@ export async function runStart(options: StartOptions): Promise<void> {
       console.log(chalk.green(`Daemon starting in background (PID ${startup.pid ?? 'unknown'}).`))
       console.log(chalk.dim(`Logs: ${startup.logPath}`))
     } catch (err) {
-      const message = err instanceof Error ? err.message : String(err)
-      console.error(chalk.red(message))
-      process.exit(1)
+      exitWithError(getErrorMessage(err))
     }
     return
   }
@@ -94,18 +93,15 @@ export async function runStart(options: StartOptions): Promise<void> {
     logger = createRootLogger(persistedConfig)
     config = loadConfig(paseoHome, { cli: toCliOverrides(options) })
   } catch (err) {
-    const message = err instanceof Error ? err.message : String(err)
-    console.error(chalk.red(message))
-    process.exit(1)
+    exitWithError(getErrorMessage(err))
   }
 
   let daemon: Awaited<ReturnType<typeof createPaseoDaemon>>
   try {
     daemon = await createPaseoDaemon(config, logger)
   } catch (err) {
-    const message = err instanceof Error ? err.message : String(err)
-    console.error(chalk.red(`Failed to initialize daemon: ${message}`))
-    process.exit(1)
+    const message = getErrorMessage(err)
+    exitWithError(`Failed to initialize daemon: ${message}`)
   }
 
   let shuttingDown = false
@@ -140,8 +136,12 @@ export async function runStart(options: StartOptions): Promise<void> {
   try {
     await daemon.start()
   } catch (err) {
-    const message = err instanceof Error ? err.message : String(err)
-    console.error(chalk.red(`Failed to start daemon: ${message}`))
+    const message = getErrorMessage(err)
+    exitWithError(`Failed to start daemon: ${message}`)
+  }
+}
+
+function exitWithError(message: string): never {
+  console.error(chalk.red(message))
   process.exit(1)
 }
-}

packages/cli/src/utils/errors.ts

@@ -0,0 +1,10 @@
+/**
+ * Convert unknown thrown values into a user-safe error string.
+ */
+export function getErrorMessage(error: unknown): string {
+  if (error instanceof Error) {
+    return error.message
+  }
+
+  return String(error)
+}

packages/cli/tests/19-errors-utils.test.ts

@@ -0,0 +1,22 @@
+#!/usr/bin/env npx tsx
+
+import assert from 'node:assert'
+import { getErrorMessage } from '../src/utils/errors.js'
+
+console.log('=== Error Utils ===\n')
+
+{
+  console.log('Test 1: returns Error.message for Error instances')
+  assert.strictEqual(getErrorMessage(new Error('boom')), 'boom')
+  console.log('✓ returns Error.message\n')
+}
+
+{
+  console.log('Test 2: stringifies non-Error values')
+  assert.strictEqual(getErrorMessage('plain string'), 'plain string')
+  assert.strictEqual(getErrorMessage(42), '42')
+  assert.strictEqual(getErrorMessage(null), 'null')
+  console.log('✓ stringifies non-Error values\n')
+}
+
+console.log('=== All error utility tests passed ===')