feat(app): export createClientEffect from package entry point and add CI integration test

- Export createClientEffect and createUniversalDispatcher from src/index.ts
  so `import { createClientEffect, type ClientOptions } from "openapi-effect"` works
- Add integration test verifying the exact user DSL snippet from issue #5:
  createClientEffect<paths>(options).POST("/api/auth/login", { body: credentials })
- 5 new tests: POST with body, yield* pattern, error handling, GET, 204 no-content

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: konard

packages/app/src/index.ts

@@ -14,7 +14,7 @@ export type {
   StrictApiClient,
   StrictApiClientWithDispatchers
 } from "./shell/api-client/create-client.js"
-export { registerDefaultDispatchers } from "./shell/api-client/create-client.js"
+export { createClientEffect, registerDefaultDispatchers } from "./shell/api-client/create-client.js"
 
 // Core types (for advanced type manipulation)
 // Effect Channel Design:
@@ -48,6 +48,7 @@ export type { Decoder, Dispatcher, RawResponse, StrictClient, StrictRequestInit
 export {
   createDispatcher,
   createStrictClient,
+  createUniversalDispatcher,
   executeRequest,
   parseJSON,
   unexpectedContentType,

packages/app/tests/api-client/create-client-effect-integration.test.ts

@@ -0,0 +1,185 @@
+// CHANGE: Integration test verifying the exact user DSL snippet from issue #5
+// WHY: Ensure the import/usage pattern requested by the user compiles and works end-to-end
+// QUOTE(ТЗ): "import { createClientEffect, type ClientOptions } from 'openapi-effect' ... apiClientEffect.POST('/api/auth/login', { body: credentials })"
+// REF: issue-5, PR#6 comment from skulidropek
+// SOURCE: n/a
+// FORMAT THEOREM: ∀ Paths, options: createClientEffect<Paths>(options).POST(path, { body }) → Effect<ApiSuccess, ApiFailure, HttpClient>
+// PURITY: SHELL
+// EFFECT: Effect<void, never, never>
+// INVARIANT: The exact user snippet compiles and produces correct runtime behavior
+// COMPLEXITY: O(1) per test
+
+import * as HttpClient from "@effect/platform/HttpClient"
+import * as HttpClientResponse from "@effect/platform/HttpClientResponse"
+import { Effect, Either, Layer } from "effect"
+import { describe, expect, it } from "vitest"
+
+// CHANGE: Import via the package's main entry point (src/index.ts)
+// WHY: Verify the user's import pattern `from "openapi-effect"` resolves correctly
+// REF: issue-5
+import { createClientEffect } from "../../src/index.js"
+import type { ClientOptions } from "../../src/index.js"
+
+// CHANGE: Import paths from the auth OpenAPI schema
+// WHY: Match the user's pattern `import type { paths } from "./openapi.d.ts"`
+// REF: issue-5
+import type { paths } from "../../src/core/api/openapi.js"
+
+/**
+ * Create a mock HttpClient layer that returns a fixed response
+ *
+ * @pure true - returns pure layer
+ */
+const createMockHttpClientLayer = (
+  status: number,
+  headers: Record<string, string>,
+  body: string
+): Layer.Layer<HttpClient.HttpClient> =>
+  Layer.succeed(
+    HttpClient.HttpClient,
+    HttpClient.make(
+      (request) =>
+        Effect.succeed(
+          HttpClientResponse.fromWeb(
+            request,
+            status === 204 || status === 304
+              ? new Response(null, { status, headers: new Headers(headers) })
+              : new Response(body, { status, headers: new Headers(headers) })
+          )
+        )
+    )
+  )
+
+/**
+ * Test fixtures for integration tests
+ *
+ * @pure true - immutable test data factories
+ */
+const fixtures = {
+  loginBody: () => ({ email: "user@example.com", password: `test-${Date.now()}` }),
+  wrongLoginBody: () => ({ email: "user@example.com", password: `wrong-${Date.now()}` })
+} as const
+
+// =============================================================================
+// SECTION: Exact user snippet integration test (CI/CD check)
+// =============================================================================
+
+describe("CI/CD: exact user snippet from issue #5", () => {
+  // --- The exact code from the user's PR comment ---
+  const clientOptions: ClientOptions = {
+    baseUrl: "https://petstore.example.com",
+    credentials: "include"
+  }
+  const apiClientEffect = createClientEffect<paths>(clientOptions)
+
+  it("should compile and execute: apiClientEffect.POST('/api/auth/login', { body: credentials })", () =>
+    Effect.gen(function*() {
+      const credentials = fixtures.loginBody()
+      const successBody = JSON.stringify({
+        id: "550e8400-e29b-41d4-a716-446655440000",
+        email: "user@example.com",
+        firstName: "John",
+        lastName: "Doe",
+        profileImageUrl: null,
+        emailVerified: true,
+        phoneVerified: false
+      })
+
+      // Type-safe — path, method, and body all enforced at compile time
+      const result = yield* Effect.either(
+        apiClientEffect.POST("/api/auth/login", {
+          body: credentials
+        }).pipe(
+          Effect.provide(
+            createMockHttpClientLayer(200, { "content-type": "application/json" }, successBody)
+          )
+        )
+      )
+
+      expect(Either.isRight(result)).toBe(true)
+      if (Either.isRight(result)) {
+        expect(result.right.status).toBe(200)
+        expect(result.right.contentType).toBe("application/json")
+        const body = result.right.body as { id: string; email: string }
+        expect(body.email).toBe("user@example.com")
+      }
+    }).pipe(Effect.runPromise))
+
+  it("should compile and execute: yield* apiClientEffect.POST (inside Effect.gen)", () =>
+    Effect.gen(function*() {
+      const credentials = fixtures.loginBody()
+      const successBody = JSON.stringify({
+        id: "550e8400-e29b-41d4-a716-446655440000",
+        email: "user@example.com"
+      })
+
+      // This verifies the `yield*` pattern from the user's snippet
+      const result = yield* apiClientEffect.POST("/api/auth/login", {
+        body: credentials
+      }).pipe(
+        Effect.provide(
+          createMockHttpClientLayer(200, { "content-type": "application/json" }, successBody)
+        )
+      )
+
+      expect(result.status).toBe(200)
+      expect(result.contentType).toBe("application/json")
+      const body = result.body as { email: string }
+      expect(body.email).toBe("user@example.com")
+    }).pipe(Effect.runPromise))
+
+  it("should handle error responses via Effect error channel", () =>
+    Effect.gen(function*() {
+      const credentials = fixtures.wrongLoginBody()
+      const errorBody = JSON.stringify({ error: "invalid_credentials" })
+
+      const result = yield* Effect.either(
+        apiClientEffect.POST("/api/auth/login", {
+          body: credentials
+        }).pipe(
+          Effect.provide(
+            createMockHttpClientLayer(401, { "content-type": "application/json" }, errorBody)
+          )
+        )
+      )
+
+      expect(Either.isLeft(result)).toBe(true)
+      if (Either.isLeft(result)) {
+        expect(result.left).toMatchObject({
+          _tag: "HttpError",
+          status: 401
+        })
+      }
+    }).pipe(Effect.runPromise))
+
+  it("should work with GET requests (no body required)", () =>
+    Effect.gen(function*() {
+      const profileBody = JSON.stringify({
+        id: "550e8400-e29b-41d4-a716-446655440000",
+        email: "user@example.com"
+      })
+
+      const result = yield* apiClientEffect.GET("/api/auth/me").pipe(
+        Effect.provide(
+          createMockHttpClientLayer(200, { "content-type": "application/json" }, profileBody)
+        )
+      )
+
+      expect(result.status).toBe(200)
+      const body = result.body as { email: string }
+      expect(body.email).toBe("user@example.com")
+    }).pipe(Effect.runPromise))
+
+  it("should handle 204 no-content responses", () =>
+    Effect.gen(function*() {
+      const result = yield* apiClientEffect.POST("/api/auth/logout").pipe(
+        Effect.provide(
+          createMockHttpClientLayer(204, {}, "")
+        )
+      )
+
+      expect(result.status).toBe(204)
+      expect(result.contentType).toBe("none")
+      expect(result.body).toBeUndefined()
+    }).pipe(Effect.runPromise))
+})