feat(web): configure DeepSeek during onboarding

packages/client/connection/src/client/fixture.ts

@@ -588,7 +588,11 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
     { provider: 'deepseek-official', model: 'deepseek-v4-flash' },
   ]))
   /** Credential store double: set/unset flip the describe badge, values never read back. */
-  const fixtureCredentials = new Map<string, string>()
+  const fixtureCredentials = new Map<string, true>([
+    // The assembled fixture represents an already-configured shipped
+    // DeepSeek route so unrelated GUI journeys do not enter first-run setup.
+    ['DEEPSEEK_API_KEY', true],
+  ])
   const nextTurn = new Map<SessionId, number>([[sid('fx-alpha'), 60]])
   let nextSession = 1
   let nextRpc = 1
@@ -1284,19 +1288,26 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
       },
     },
     settings: {
-      // The fixture registers no namespaces yet: the Models surface renders
-      // its provider list from llm.providers alone, and a real settings form
-      // rides the HTTP transport (a hand-written schema envelope here would
-      // drift from schemastery's real serialization).
-      describe: request => ok(request, { writable: true, namespaces: [] }),
+      // Only the resolved DeepSeek address needed by first-run readiness is
+      // represented here; real schema-driven forms ride the HTTP transport.
+      describe: request => ok(request, {
+        writable: true,
+        namespaces: [{
+          ns: 'llm-deepseek',
+          schema: {},
+          value: { apiKeyEnv: 'DEEPSEEK_API_KEY' },
+          applies: 'live',
+          secrets: [{ path: ['apiKey'], set: false }],
+        }],
+      }),
       update: request => err(request, {
         code: 'settings-rejected',
-        message: 'fixture: no settings namespaces are registered',
+        message: 'fixture: the minimal readiness settings descriptor is read-only',
         details: { ns: request.payload.ns },
       }),
       replace: request => err(request, {
         code: 'settings-rejected',
-        message: 'fixture: no settings namespaces are registered',
+        message: 'fixture: the minimal readiness settings descriptor is read-only',
         details: { ns: request.payload.ns },
       }),
     },
@@ -1309,7 +1320,7 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
         }])),
       }),
       set: (request) => {
-        fixtureCredentials.set(request.payload.ref, request.payload.value)
+        fixtureCredentials.set(request.payload.ref, true)
         return ok(request, {})
       },
       unset: (request) => {

packages/client/connection/tests/fixture.spec.ts

@@ -108,6 +108,36 @@ describe('createFixtureApi', () => {
     expect(JSON.stringify(after.result.value.events)).toContain('openai/gpt-5')
   })
 
+  it('serves configured DeepSeek readiness and keeps credential values write-only', async () => {
+    const api = createFixtureApi()
+    const settings = await api.settings.describe(req({}))
+    if (!settings.result.ok) throw new Error('settings describe failed')
+    expect(settings.result.value.namespaces).toMatchObject([{
+      ns: 'llm-deepseek',
+      value: { apiKeyEnv: 'DEEPSEEK_API_KEY' },
+      secrets: [{ path: ['apiKey'], set: false }],
+    }])
+
+    const initial = await api.credentials.describe(req({ refs: ['DEEPSEEK_API_KEY', 'TEST_API_KEY'] }))
+    if (!initial.result.ok) throw new Error('credential describe failed')
+    expect(initial.result.value.credentials).toEqual({
+      DEEPSEEK_API_KEY: { configured: true, source: 'file', writable: true },
+      TEST_API_KEY: { configured: false, writable: true },
+    })
+    await api.credentials.set(req({ ref: 'TEST_API_KEY', value: 'write-only-fixture-secret' }))
+    const configured = await api.credentials.describe(req({ refs: ['TEST_API_KEY'] }))
+    if (!configured.result.ok) throw new Error('credential describe failed')
+    expect(configured.result.value.credentials.TEST_API_KEY).toEqual({
+      configured: true,
+      source: 'file',
+      writable: true,
+    })
+    await api.credentials.unset(req({ ref: 'TEST_API_KEY' }))
+    const cleared = await api.credentials.describe(req({ refs: ['TEST_API_KEY'] }))
+    if (!cleared.result.ok) throw new Error('credential describe failed')
+    expect(cleared.result.value.credentials.TEST_API_KEY).toEqual({ configured: false, writable: true })
+  })
+
   it('emits the todo/write snapshot at the real tool boundary: between tool/call and tool/result, timestamps monotonic', async () => {
     const api = createFixtureApi()
     const tail = await api.sessions.history(req({ sessionId: sid('fx-alpha'), maxMessages: 10 }))