test: isolate shared-state test suites for CI stability

- add dependency injection to export-command, binary-manager,
  codex-plan-compatibility, config-command, and usage-syncer
- override process.exit in api-export test to prevent silent
  termination in Bun's parallel test runner
- harden test-environment bootstrap with process.env isolation
- fix auth middleware to avoid config upgrade during checks

tests/unit/commands/proxy-lifecycle-subcommand.test.ts

@@ -1,62 +1,33 @@
-import { afterEach, describe, expect, it, mock } from 'bun:test';
+import { describe, expect, it } from 'bun:test';
 import { CLIPROXY_DEFAULT_PORT } from '../../../src/cliproxy/config/port-manager';
-
-type MockUnifiedConfig = {
-  cliproxy_server?: {
-    local?: {
-      port?: number;
-    };
-  };
-};
-
-function mockUnifiedConfig(config: MockUnifiedConfig): void {
-  mock.module('../../../src/config/unified-config-loader', () => ({
-    loadOrCreateUnifiedConfig: () => config,
-  }));
-}
-
-async function loadResolveLifecyclePort() {
-  const mod = await import(
-    `../../../src/commands/cliproxy/resolve-lifecycle-port?proxy-lifecycle-port=${Date.now()}-${Math.random()}`
-  );
-  return mod.resolveLifecyclePort;
-}
+import { resolveLifecyclePort } from '../../../src/commands/cliproxy/resolve-lifecycle-port';
 
 describe('resolveLifecyclePort', () => {
-  afterEach(() => {
-    mock.restore();
-  });
-
-  it('uses configured cliproxy_server.local.port', async () => {
-    mockUnifiedConfig({
-      cliproxy_server: {
-        local: {
-          port: 9456,
+  it('uses configured cliproxy_server.local.port', () => {
+    expect(
+      resolveLifecyclePort({
+        cliproxy_server: {
+          local: {
+            port: 9456,
+          },
         },
-      },
-    });
-
-    const resolveLifecyclePort = await loadResolveLifecyclePort();
-    expect(resolveLifecyclePort()).toBe(9456);
+      })
+    ).toBe(9456);
   });
 
-  it('falls back to default port when configured local port is invalid', async () => {
-    mockUnifiedConfig({
-      cliproxy_server: {
-        local: {
-          port: 70000,
+  it('falls back to default port when configured local port is invalid', () => {
+    expect(
+      resolveLifecyclePort({
+        cliproxy_server: {
+          local: {
+            port: 70000,
+          },
         },
-      },
-    });
-
-    const resolveLifecyclePort = await loadResolveLifecyclePort();
-    expect(resolveLifecyclePort()).toBe(CLIPROXY_DEFAULT_PORT);
+      })
+    ).toBe(CLIPROXY_DEFAULT_PORT);
   });
 
-  it('falls back to default port when config file is missing', async () => {
-    mockUnifiedConfig({});
-
-    const resolveLifecyclePort = await loadResolveLifecyclePort();
-    expect(resolveLifecyclePort()).toBe(CLIPROXY_DEFAULT_PORT);
+  it('falls back to default port when config file is missing', () => {
+    expect(resolveLifecyclePort({})).toBe(CLIPROXY_DEFAULT_PORT);
   });
 });