test: add regression test for cask inclusion in SelectedPkgs

Adds TestRunCustomInstall_IncludesCasksInSelectedPkgs to verify that
GUI apps (casks) from remote configs are properly added to SelectedPkgs.

This prevents regression of the bug where casks were silently skipped
during remote config installation.

Related to #17

Author: Jerry Xie

internal/installer/installer_test.go

@@ -125,10 +125,41 @@ func TestCheckDependencies_DryRunSkipsEverything(t *testing.T) {
 	}
 	opts := cfg.ToInstallOptions()
 	st := cfg.ToInstallState()
-	err := checkDependencies(opts, st)
+	err := runCustomInstall(opts, st)
 	assert.NoError(t, err)
 }
 
+// TestRunCustomInstall_IncludesCasksInSelectedPkgs verifies that GUI apps (casks)
+// from remote config are added to SelectedPkgs so they get installed.
+// Regression test for: https://github.com/openbootdotdev/openboot/issues/17
+func TestRunCustomInstall_IncludesCasksInSelectedPkgs(t *testing.T) {
+	tmpDir := t.TempDir()
+	t.Setenv("HOME", tmpDir)
+
+	cfg := &config.Config{
+		DryRun: true,
+		Shell:  "skip",
+		Macos:  "skip",
+		RemoteConfig: &config.RemoteConfig{
+			Username: "testuser",
+			Slug:     "testconfig",
+			Packages: config.PackageEntryList{{Name: "git"}, {Name: "curl"}},
+			Casks:    config.PackageEntryList{{Name: "visual-studio-code"}, {Name: "firefox"}},
+		},
+	}
+
+	opts := cfg.ToInstallOptions()
+	st := cfg.ToInstallState()
+	err := runCustomInstall(opts, st)
+	assert.NoError(t, err)
+
+	// Verify both packages and casks are in SelectedPkgs
+	assert.Contains(t, st.SelectedPkgs, "git", "CLI package should be in SelectedPkgs")
+	assert.Contains(t, st.SelectedPkgs, "curl", "CLI package should be in SelectedPkgs")
+	assert.Contains(t, st.SelectedPkgs, "visual-studio-code", "GUI app (cask) should be in SelectedPkgs")
+	assert.Contains(t, st.SelectedPkgs, "firefox", "GUI app (cask) should be in SelectedPkgs")
+}
+
 func TestRunInstall_DryRunRemoteConfig(t *testing.T) {
 	cfg := &config.Config{
 		DryRun: true,