fix(install): skip browser download when system chromium exists

tests/test_install_sh_browser_install.py

@@ -0,0 +1,35 @@
+"""Regression tests for install.sh browser setup.
+
+Browser automation is optional. The installer should not leave Hermes
+half-installed just because Playwright's managed Chromium download hangs on an
+unsupported distribution.
+"""
+
+from pathlib import Path
+
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+INSTALL_SH = REPO_ROOT / "scripts" / "install.sh"
+
+
+def test_install_script_skips_playwright_download_when_system_browser_exists() -> None:
+    text = INSTALL_SH.read_text()
+
+    assert "find_system_browser()" in text
+    assert "google-chrome google-chrome-stable chromium chromium-browser chrome" in text
+    assert "Skipping Playwright browser download; Hermes will use the system browser." in text
+
+
+def test_install_script_persists_system_browser_for_agent_browser() -> None:
+    text = INSTALL_SH.read_text()
+
+    assert "configure_browser_env_from_system_browser()" in text
+    assert "AGENT_BROWSER_EXECUTABLE_PATH=$browser_path" in text
+
+
+def test_playwright_installs_are_timeout_guarded() -> None:
+    text = INSTALL_SH.read_text()
+
+    assert "run_browser_install_with_timeout()" in text
+    assert "run_browser_install_with_timeout 600 npx playwright install chromium" in text
+    assert "run_browser_install_with_timeout 600 npx playwright install --with-deps chromium" in text

tests/tools/test_browser_chromium_check.py

@@ -41,6 +41,16 @@ class TestChromiumSearchRoots:
 
 
 class TestChromiumInstalled:
+    def test_true_when_plain_chromium_on_path(self, monkeypatch):
+        monkeypatch.delenv("AGENT_BROWSER_EXECUTABLE_PATH", raising=False)
+        monkeypatch.setattr(
+            bt.shutil,
+            "which",
+            lambda name: "/usr/bin/chromium" if name == "chromium" else None,
+        )
+
+        assert bt._chromium_installed() is True
+
     def test_true_when_chromium_dir_present(self, monkeypatch, tmp_path):
         monkeypatch.setenv("PLAYWRIGHT_BROWSERS_PATH", str(tmp_path))
         (tmp_path / "chromium-1208").mkdir()
@@ -108,4 +118,3 @@ class TestRunBrowserCommandChromiumGuard:
     """
 
 
-