fix: strengthen termux install network prerequisites

tests/test_install_sh_termux_network_prereqs.py

@@ -0,0 +1,22 @@
+"""Regression tests for Termux network prerequisite handling in install.sh."""
+
+from pathlib import Path
+
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+INSTALL_SH = REPO_ROOT / "scripts" / "install.sh"
+
+
+def test_termux_pkg_list_includes_network_basics() -> None:
+    text = INSTALL_SH.read_text()
+    assert "local termux_pkgs=(clang rust make pkg-config libffi openssl ca-certificates curl)" in text
+
+
+def test_install_script_has_connectivity_probe_and_termux_guidance() -> None:
+    text = INSTALL_SH.read_text()
+    assert "check_network_prerequisites()" in text
+    assert "https://pypi.org/simple/" in text
+    assert "https://duckduckgo.com/" in text
+    assert "termux-change-repo" in text
+    assert "pkg install -y ca-certificates curl && pkg update" in text
+    assert "check_network_prerequisites" in text