fix(team): merge team edit --unit into the current unit policy

Gitea replaces a team's whole unit policy on edit, so
`tea team edit 5 --unit repo.wiki=write` revoked code, issue and pull
request access. team edit now merges --unit into the current policy;
--unit-replace keeps the old replacing behavior.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/teams_test.go

@@ -5,6 +5,7 @@ package app
 
 import (
 	"context"
+	"encoding/json"
 	"net/http"
 	"testing"
 
@@ -52,3 +53,28 @@ func TestTeamDeleteNamesTheTeamAndProtectsTheOwnerTeam(t *testing.T) {
 	require.Equal(t, []string{`Delete team "devs" (ID 5) from acme?`}, prompt.confirmations)
 	require.Equal(t, []string{"/api/v1/teams/3", "/api/v1/teams/5"}, deleted)
 }
+
+func TestTeamEditMergesUnitsIntoTheCurrentPolicy(t *testing.T) {
+	var sent []map[string]any
+	server := newAuthenticatedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "/api/v1/teams/5", r.URL.Path)
+		if r.Method == http.MethodPatch {
+			var body map[string]any
+			require.NoError(t, json.NewDecoder(r.Body).Decode(&body))
+			sent = append(sent, body)
+		}
+		_, _ = w.Write([]byte(`{"id":5,"name":"devs","permission":"write","units_map":{"repo.code":"write","repo.issues":"write","repo.pulls":"write"}}`))
+	}))
+	defer server.Close()
+	deps, _, _ := serverDeps(t, server.URL)
+	require.NoError(t, Execute(context.Background(), deps, []string{"team", "edit", "5", "--unit", "repo.wiki=write", "--json"}))
+	require.NoError(t, Execute(context.Background(), deps, []string{"team", "edit", "5", "--unit", "repo.wiki=write", "--unit-replace", "--json"}))
+	require.Equal(t, []map[string]any{
+		{"units_map": map[string]any{"repo.code": "write", "repo.issues": "write", "repo.pulls": "write", "repo.wiki": "write"}},
+		{"units_map": map[string]any{"repo.wiki": "write"}},
+	}, sent)
+	err := Execute(context.Background(), deps, []string{"team", "edit", "5", "--unit-replace", "--name", "devs"})
+	require.Equal(t, clierr.Usage, clierr.ExitCode(err), "%v", err)
+	require.ErrorContains(t, err, "--unit-replace requires --unit")
+	require.Len(t, sent, 2)
+}