improvement(self-host): simplify capability setup configuration (#6230)

* feat(self-host): add capability-aware setup

* fix(self-host): preserve capability compatibility

* fix(copilot): honor preview availability server-side

* improvement(self-host): centralize capability resolution

* fix(self-host): preserve integration availability paths

* fix(testing): align capability-aware config mocks

* improvement(self-host): simplify capability setup configuration

* fix(setup): preserve unowned storage overrides

* fix(self-host): reconcile storage and allowlists

* fix(integrations): preserve connect deep links

scripts/setup/capability-setup.test.ts

@@ -0,0 +1,24 @@
+import { describe, expect, it } from 'bun:test'
+import type { SetupFieldPrompt } from './capability-config.ts'
+import { formatCapabilitySetupFieldMessage, markCurrentlyUsed } from './capability-setup.ts'
+
+describe('capability setup presentation', () => {
+  it('marks the effective option as currently used without replacing its hint', () => {
+    expect(markCurrentlyUsed('paste an API key', true)).toBe('paste an API key · Currently used')
+    expect(markCurrentlyUsed(undefined, true)).toBe('Currently used')
+    expect(markCurrentlyUsed('paste an API key', false)).toBe('paste an API key')
+  })
+
+  it('marks existing fields and explains how secrets are preserved', () => {
+    const prompt: SetupFieldPrompt = {
+      type: 'field',
+      key: 'RESEND_API_KEY',
+      input: 'secret',
+    }
+
+    expect(formatCapabilitySetupFieldMessage(prompt, true, true)).toBe(
+      'RESEND_API_KEY (Currently used); leave empty to keep it'
+    )
+    expect(formatCapabilitySetupFieldMessage(prompt, false, true)).toBe('RESEND_API_KEY')
+  })
+})