feat(client): add root promise entrypoint

packages/docs/build/client.mdx

@@ -16,22 +16,15 @@ network. Its types and methods are generated from the same contract as the
 ## Install
 
 ```sh
-bun add @opencode-ai/client
+bun add @opencode-ai/client@next
 ```
 
-The package has two entrypoints:
-
-- `@opencode-ai/client/promise` uses `fetch` and returns Promises or async
-  iterables. It has no Effect runtime dependency.
-- `@opencode-ai/client/effect` returns Effects and Streams, decodes values into
-  the V2 schema types, and requires an `HttpClient` service from Effect.
-
-## Promise client
+## Create a client
 
 Create a client with the server URL, then call methods grouped by API resource:
 
 ```ts
-import { OpenCode } from "@opencode-ai/client/promise"
+import { OpenCode } from "@opencode-ai/client"
 
 const client = OpenCode.make({
   baseUrl: "http://localhost:4096",
@@ -47,11 +40,28 @@ await client.session.prompt({
 })
 ```
 
+## Headers and requests
+
 Pass default authentication or application headers to `OpenCode.make` with
 `headers`. You can also supply a custom `fetch` implementation. Each operation
 accepts request options as its final argument for an `AbortSignal` or
 per-request headers.
 
+```ts
+const client = OpenCode.make({
+  baseUrl: "https://opencode.example.com",
+  headers: {
+    authorization: `Bearer ${process.env.OPENCODE_TOKEN}`,
+  },
+})
+
+await client.session.list(undefined, {
+  signal: AbortSignal.timeout(10_000),
+})
+```
+
+## Stream events
+
 Streaming endpoints return async iterables:
 
 ```ts
@@ -60,11 +70,17 @@ for await (const event of client.event.subscribe()) {
 }
 ```
 
-## Effect client
+## Effect
 
-Install the `effect` peer dependency when using the Effect entrypoint. The
-client uses canonical V2 values such as `Location.Ref` and `Session.ID`, and
-returns typed failures in the Effect error channel.
+OpenCode provides a first-class Effect client through the
+`@opencode-ai/client/effect` entrypoint. It returns typed Effects and Streams
+and decodes responses into OpenCode schema values.
+
+```sh
+bun add @opencode-ai/client@next effect
+```
+
+### Create a client
 
 ```ts
 import { AbsolutePath, Location, OpenCode } from "@opencode-ai/client/effect"
@@ -89,3 +105,41 @@ const session = await Effect.runPromise(
 
 Streaming operations, including `client.event.subscribe()` and
 `client.session.log(...)`, return Effect `Stream` values.
+
+### Service
+
+`Service` discovers and manages the local OpenCode background service from a
+Node application:
+
+- `Service.discover()` returns a healthy registered endpoint without starting
+  a process.
+- `Service.start()` reuses a compatible service or starts one when needed.
+- `Service.stop()` stops the registered service.
+- `Service.headers(endpoint)` creates the authentication headers for a client.
+
+```sh
+bun add @effect/platform-node
+```
+
+```ts
+import { NodeFileSystem } from "@effect/platform-node"
+import { OpenCode, Service } from "@opencode-ai/client/effect"
+import { Effect } from "effect"
+import { FetchHttpClient } from "effect/unstable/http"
+
+const program = Effect.gen(function* () {
+  const endpoint = yield* Service.start()
+  const client = yield* OpenCode.make({
+    baseUrl: endpoint.url,
+    headers: Service.headers(endpoint),
+  })
+  return yield* client.health.get()
+})
+
+const health = await Effect.runPromise(
+  program.pipe(
+    Effect.provide(FetchHttpClient.layer),
+    Effect.provide(NodeFileSystem.layer),
+  ),
+)
+```