test: wire vitest workspace aliases so tests consume source, not dist

Adds a shared vitest.aliases.ts that maps every @arcp/* import to the
package's src/ entrypoint, and references it from each package's
vitest.config.ts. Lets the stdio transport integration test (and any
future cross-package test) stay correct even when dist is stale or
absent. Adjusts the test to pass cwd and TSX_TSCONFIG_PATH so the
spawned tsx subprocess resolves the workspace tsconfig.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Nick Ficano

packages/client/vitest.config.ts

@@ -1,6 +1,11 @@
 import { defineConfig } from "vitest/config";
 
+import { arcpWorkspaceAliases } from "../../vitest.aliases.js";
+
 export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
   test: {
     include: ["test/**/*.test.ts"],
     environment: "node",

packages/core/vitest.config.ts

@@ -1,6 +1,11 @@
 import { defineConfig } from "vitest/config";
 
+import { arcpWorkspaceAliases } from "../../vitest.aliases.js";
+
 export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
   test: {
     include: ["test/**/*.test.ts"],
     environment: "node",

packages/middleware/bun/vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
+export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
+  test: {
+    include: ["test/**/*.test.ts"],
+    environment: "node",
+  },
+});

packages/middleware/express/vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
+export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
+  test: {
+    include: ["test/**/*.test.ts"],
+    environment: "node",
+  },
+});

packages/middleware/fastify/vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
+export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
+  test: {
+    include: ["test/**/*.test.ts"],
+    environment: "node",
+  },
+});

packages/middleware/hono/vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
+export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
+  test: {
+    include: ["test/**/*.test.ts"],
+    environment: "node",
+  },
+});

packages/middleware/node/vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
+export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
+  test: {
+    include: ["test/**/*.test.ts"],
+    environment: "node",
+  },
+});

packages/middleware/otel/vitest.config.ts

@@ -1,6 +1,11 @@
 import { defineConfig } from "vitest/config";
 
+import { arcpWorkspaceAliases } from "../../../vitest.aliases.js";
+
 export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
   test: {
     include: ["test/**/*.test.ts"],
     environment: "node",

packages/runtime/vitest.config.ts

@@ -1,6 +1,11 @@
 import { defineConfig } from "vitest/config";
 
+import { arcpWorkspaceAliases } from "../../vitest.aliases.js";
+
 export default defineConfig({
+  resolve: {
+    alias: arcpWorkspaceAliases,
+  },
   test: {
     include: ["test/**/*.test.ts"],
     environment: "node",

packages/sdk/test/integration/transports.test.ts

@@ -17,6 +17,8 @@ import {
 } from "@arcp/sdk";
 
 const here = path.dirname(fileURLToPath(import.meta.url));
+const sdkRoot = path.resolve(here, "..", "..");
+const workspaceRoot = path.resolve(sdkRoot, "..", "..");
 
 interface TransportFixture {
   name: string;
@@ -75,9 +77,7 @@ const fixtures: TransportFixture[] = [
     name: "stdio",
     async setup() {
       const tsxBin = path.resolve(
-        here,
-        "..",
-        "..",
+        sdkRoot,
         "node_modules",
         ".bin",
         "tsx",
@@ -92,6 +92,11 @@ const fixtures: TransportFixture[] = [
         tsxBin,
         [runtimeScript, ":memory:"],
         {
+          cwd: sdkRoot,
+          env: {
+            ...process.env,
+            TSX_TSCONFIG_PATH: path.join(workspaceRoot, "tsconfig.base.json"),
+          },
           stdio: ["pipe", "pipe", "pipe"],
         },
       );