test: add CI workflow and fix flaky network tests

- Add .github/workflows/test.yml for PR testing
- Skip network-dependent tests when CI=true to avoid flakiness
- Network tests still run locally for full coverage

Author: johnlindquist

.github/workflows/test.yml

@@ -0,0 +1,24 @@
+name: Test
+
+on:
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    name: Run Tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Bun
+        uses: oven-sh/setup-bun@v2
+
+      - name: Install dependencies
+        run: bun install
+
+      - name: Run tests
+        run: bun test
+        env:
+          CI: true

src/fetch.test.ts

@@ -1,4 +1,8 @@
-import { describe, it, expect, mock, beforeEach, afterEach } from "bun:test";
+import { describe, it, expect, mock, beforeEach, afterEach, test } from "bun:test";
+
+// Skip network-dependent tests in CI environments to avoid flakiness
+const isCI = process.env.CI === "true";
+const describeNetwork = isCI ? describe.skip : describe;
 import {
   fetchWithTimeout,
   fetchWithRetry,
@@ -135,7 +139,7 @@ describe("fetch utilities", () => {
     });
   });
 
-  describe("fetchWithTimeout", () => {
+  describeNetwork("fetchWithTimeout", () => {
     it("successfully fetches when request completes before timeout", async () => {
       // Use a real endpoint that responds quickly
       const response = await fetchWithTimeout("https://httpbin.org/get", {
@@ -156,13 +160,15 @@ describe("fetch utilities", () => {
         expect((error as FetchTimeoutError).message).toContain("timed out after 100ms");
       }
     });
+  });
 
+  describe("fetchWithTimeout constants", () => {
     it("uses default timeout when not specified", () => {
       expect(DEFAULT_TIMEOUT_MS).toBe(10000);
     });
   });
 
-  describe("fetchWithRetry", () => {
+  describeNetwork("fetchWithRetry", () => {
     it("succeeds on first attempt for successful requests", async () => {
       const response = await fetchWithRetry("https://httpbin.org/get", {
         retry: { maxRetries: 3 },
@@ -183,7 +189,9 @@ describe("fetch utilities", () => {
       });
       expect(response.ok).toBe(true);
     });
+  });
 
+  describe("fetchWithRetry constants", () => {
     it("uses default retry config when not specified", () => {
       expect(DEFAULT_RETRY_CONFIG.maxRetries).toBe(3);
       expect(DEFAULT_RETRY_CONFIG.initialDelayMs).toBe(1000);
@@ -192,7 +200,7 @@ describe("fetch utilities", () => {
     });
   });
 
-  describe("resilientFetch", () => {
+  describeNetwork("resilientFetch", () => {
     it("successfully fetches with both timeout and retry protection", async () => {
       const response = await resilientFetch("https://httpbin.org/get", {
         timeoutMs: 10000,
@@ -254,7 +262,7 @@ describe("fetch utilities", () => {
     });
   });
 
-  describe("integration with markdown-agent use cases", () => {
+  describeNetwork("integration with markdown-agent use cases", () => {
     it("fetches GitHub raw content", async () => {
       // Test fetching a well-known, stable GitHub file
       const response = await resilientFetch(