fix: address PR review comments for podman-cpu-memory-env

Claude review on #774 flagged:
- readMachineResources/readPositiveInt had no direct test coverage
  (FakePodmanRuntime overrides initMachine entirely, so the env
  parsing path was dead code in the test suite).
- ensureReady and initMachine both logged 'Initializing Podman
  machine...' one after the other — two lines for one operation.

Fixes:
- Export readMachineResources and add 4 unit tests covering defaults,
  valid parse, non-numeric fallback, and zero/negative fallback.
- Reword the initMachine log from a duplicate headline to a concise
  resource-allocation detail ('Allocating 4 CPUs, 4096 MB RAM') that
  complements the 'Initializing Podman machine...' headline emitted by
  ensureReady.

packages/browseros-agent/apps/server/src/api/services/openclaw/podman-runtime.ts

@@ -28,7 +28,7 @@ function readPositiveInt(value: string | undefined, fallback: number): number {
   return Number.isFinite(parsed) && parsed > 0 ? parsed : fallback
 }
 
-function readMachineResources(): { cpus: number; memoryMb: number } {
+export function readMachineResources(): { cpus: number; memoryMb: number } {
   return {
     cpus: readPositiveInt(
       process.env.BROWSEROS_PODMAN_CPUS,
@@ -114,7 +114,7 @@ export class PodmanRuntime {
     if (isLinux) return
 
     const { cpus, memoryMb } = readMachineResources()
-    onLog?.(`Initializing Podman machine (${cpus} CPUs, ${memoryMb} MB RAM)`)
+    onLog?.(`Allocating ${cpus} CPUs, ${memoryMb} MB RAM`)
 
     const proc = Bun.spawn(
       [

packages/browseros-agent/apps/server/tests/api/services/openclaw/podman-runtime.test.ts

@@ -12,6 +12,7 @@ import {
   configurePodmanRuntime,
   getPodmanRuntime,
   PodmanRuntime,
+  readMachineResources,
   resolveBundledPodmanPath,
 } from '../../../../src/api/services/openclaw/podman-runtime'
 
@@ -167,3 +168,46 @@ describe('podman runtime', () => {
     expect(runtime.startCalls).toBe(1)
   })
 })
+
+describe('readMachineResources', () => {
+  const ORIGINAL_CPUS = process.env.BROWSEROS_PODMAN_CPUS
+  const ORIGINAL_MEMORY = process.env.BROWSEROS_PODMAN_MEMORY_MB
+
+  afterEach(() => {
+    restoreEnv('BROWSEROS_PODMAN_CPUS', ORIGINAL_CPUS)
+    restoreEnv('BROWSEROS_PODMAN_MEMORY_MB', ORIGINAL_MEMORY)
+  })
+
+  it('returns defaults when env vars are unset', () => {
+    delete process.env.BROWSEROS_PODMAN_CPUS
+    delete process.env.BROWSEROS_PODMAN_MEMORY_MB
+
+    expect(readMachineResources()).toEqual({ cpus: 4, memoryMb: 4096 })
+  })
+
+  it('parses valid env values', () => {
+    process.env.BROWSEROS_PODMAN_CPUS = '6'
+    process.env.BROWSEROS_PODMAN_MEMORY_MB = '8192'
+
+    expect(readMachineResources()).toEqual({ cpus: 6, memoryMb: 8192 })
+  })
+
+  it('falls back to defaults for non-numeric input', () => {
+    process.env.BROWSEROS_PODMAN_CPUS = 'abc'
+    process.env.BROWSEROS_PODMAN_MEMORY_MB = ''
+
+    expect(readMachineResources()).toEqual({ cpus: 4, memoryMb: 4096 })
+  })
+
+  it('falls back to defaults for zero and negative values', () => {
+    process.env.BROWSEROS_PODMAN_CPUS = '0'
+    process.env.BROWSEROS_PODMAN_MEMORY_MB = '-512'
+
+    expect(readMachineResources()).toEqual({ cpus: 4, memoryMb: 4096 })
+  })
+})
+
+function restoreEnv(key: string, value: string | undefined): void {
+  if (value === undefined) delete process.env[key]
+  else process.env[key] = value
+}