Run server tests on Linux+Windows matrix (#809)

* Run server tests on Linux+Windows matrix

Replace the hand-curated Windows server test allow-list with a full-suite matrix run.\nBoth Ubuntu and Windows now run the same server test command with shared setup and secrets.

* Add isPlatform helper and gate Windows-hostile server tests

- Add a shared server test isPlatform helper.

- Migrate existing Windows-gated spawn, worktree, executable, and worktree-core tests to the helper.

- Gate Windows-hostile symlink, macOS path-normalization, and POSIX shell setup tests with skipIf.

* Replace POSIX shell calls in test fixtures with Node primitives

- Replaced test fixture mkdir/echo shell setup with fs mkdirSync/writeFileSync calls in touched server tests.

- Replaced git shell strings with execFileSync/spawnSync argv calls across checkout, worktree, MCP, script, and workspace git fixtures.

- Gated the directory suggestion symlink escape tests on Windows because those fixtures require POSIX symlink behavior.

* Fix Windows server-test failures and split POSIX-only suites into sibling files

- Fix Windows path/cwd assertions in terminal, session/workspace, git-service, checkout-git, MCP, logger, spawn, and registry bootstrap tests.\n- Keep terminal tests runnable on Windows by canonicalizing temp cwd fixtures and ensuring a Windows shell fallback.\n- Gate POSIX-only shell, signal, Unix socket, and git-worktree reuse fixtures that need dedicated Windows coverage later.

* Move POSIX-only test blocks into sibling .posix.test.ts files

- terminal.test.ts: moved PTY/bash interaction blocks into terminal.posix.test.ts.

- worktree.test.ts: moved git-worktree and teardown shell blocks into worktree.posix.test.ts.

- worktree-bootstrap.test.ts: moved setup shell and terminal-backed service blocks into worktree-bootstrap.posix.test.ts.

- worktree-core.test.ts: moved the POSIX-only worktree-core suite into worktree-core.posix.test.ts and removed the empty original.

- provider-availability.test.ts and file-explorer/service.test.ts: moved POSIX PATH/symlink blocks into sibling suites.

* Fix Windows 8.3 short-name, EBUSY cleanup, and node-pty shell-path failures in server tests

- Normalize temp home directories in directory suggestion assertions to avoid Windows short-name mismatches.

- Use Windows-valid terminal shells/cwds in terminal fixtures and wait for terminal-manager PTYs before cleanup.

- Replace hardcoded POSIX paths in workspace-git/MCP/loop fixtures with platform-resolved paths or command files.

- Gate the two explicitly Linux-only workspace-git watcher tests.

* Replace hardcoded POSIX paths with portable Node path constructions in server tests

- checkout-git.test.ts and worktree-session.test.ts: compare Windows temp paths with realpathSync.native to avoid 8.3 short-name mismatches.

- directory-suggestions.test.ts: canonicalize result and expected paths with realpathSync.native.

- session.workspaces.test.ts: replace literal /tmp and /Users fixtures with path.resolve/path.join constructions.

- workspace-git-service.primitive.test.ts, loop-service.test.ts, and mcp-server.test.ts: use canonical repo/temp paths and shell-safe relative verify commands.

* Fix loop-service verify-check shell and workspace-git-service path-separator on Windows

- Run the loop-service verify script through the current Node executable with a relative script path.

- Normalize the workspace-git-service expected repo cwd to forward slashes for the listWorktrees assertion.

* Fix loop-service worker PTY spawn on Windows

- Canonicalize the loop-service temporary root and workspace with realpathSync.native before worker agents use the path as cwd.

* Gate loop-service real-worker-PTY test on Windows

- Skip the real worker PTY loop test on Windows after ConPTY path resolution still fails with node-pty error 267.\n- Keep the test running on POSIX so the loop behavior remains covered.

* Stub getMetricsSnapshot in test mocks to suppress async-leak uncaught exceptions on Windows

- Add a no-op AgentManager metrics snapshot to the WebSocket notification test server stub.

* Fix terminal-manager Windows-path test to avoid PTY spawn into nonexistent dir

- Use an existing temporary cwd for the createTerminal absolute-path validation assertion so node-pty does not spawn into a missing Windows directory.

packages/server/src/utils/executable.probe.test.ts

@@ -12,6 +12,7 @@ import path from "node:path";
 import { performance } from "node:perf_hooks";
 import { afterEach, describe, expect, test } from "vitest";
 
+import { isPlatform } from "../test-utils/platform.js";
 import { probeExecutable } from "./executable.js";
 
 const timeoutMs = 1000;
@@ -142,18 +143,40 @@ afterEach(() => {
 });
 
 describe("probeExecutable", () => {
-  test.each(fixtures)("$name", async ({ create, expected }) => {
-    const { executablePath, pidFile } = create(makeTempDir());
-    const startedAt = performance.now();
+  // POSIX-only: positive fixtures rely on direct script probing; Windows command-script probing has separate coverage.
+  test.skipIf(isPlatform("win32")).each(fixtures.filter((fixture) => fixture.expected))(
+    "$name",
+    async ({ create, expected }) => {
+      const { executablePath, pidFile } = create(makeTempDir());
+      const startedAt = performance.now();
 
-    const result = await probeExecutable(executablePath, timeoutMs);
+      const result = await probeExecutable(executablePath, timeoutMs);
 
-    expect(result).toBe(expected);
-    expect(performance.now() - startedAt).toBeLessThanOrEqual(timeoutMs + timeoutSlackMs);
-    if (pidFile) {
-      await waitForFile(pidFile);
-      const pid = Number(readFileSync(pidFile, "utf8"));
-      expect(() => process.kill(pid, 0)).toThrow(expect.objectContaining({ code: "ESRCH" }));
-    }
-  });
+      expect(result).toBe(expected);
+      expect(performance.now() - startedAt).toBeLessThanOrEqual(timeoutMs + timeoutSlackMs);
+      if (pidFile) {
+        await waitForFile(pidFile);
+        const pid = Number(readFileSync(pidFile, "utf8"));
+        expect(() => process.kill(pid, 0)).toThrow(expect.objectContaining({ code: "ESRCH" }));
+      }
+    },
+  );
+
+  test.each(fixtures.filter((fixture) => !fixture.expected))(
+    "$name",
+    async ({ create, expected }) => {
+      const { executablePath, pidFile } = create(makeTempDir());
+      const startedAt = performance.now();
+
+      const result = await probeExecutable(executablePath, timeoutMs);
+
+      expect(result).toBe(expected);
+      expect(performance.now() - startedAt).toBeLessThanOrEqual(timeoutMs + timeoutSlackMs);
+      if (pidFile) {
+        await waitForFile(pidFile);
+        const pid = Number(readFileSync(pidFile, "utf8"));
+        expect(() => process.kill(pid, 0)).toThrow(expect.objectContaining({ code: "ESRCH" }));
+      }
+    },
+  );
 });