feat(login): add status command (#1087) (#1105)

Implements #1087.

Adds `tea login status [<login name>] [-o <format>]`, which verifies the stored token for one or all configured logins and reports:

- login name/URL and default status
- whether the token is valid (via `GET /api/v1/user`)
- auth method and token expiry
- whether the git credential helper is configured

Machine-readable output is available via the usual `-o` formats with fields `name`, `url`, `user`, `valid`, `auth_method`, `token_expiry`, `helper`, and `default`.

Reviewed-on: https://gitea.com/gitea/tea/pulls/1105
Reviewed-by: bircni <bircni@icloud.com>

modules/task/login_status_test.go

@@ -0,0 +1,75 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package task
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"path/filepath"
+	"testing"
+
+	"gitea.dev/tea/modules/config"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCheckLoginStatus(t *testing.T) {
+	// Keep helper detection isolated from the developer's real git config.
+	t.Setenv("GIT_CONFIG_GLOBAL", filepath.Join(t.TempDir(), ".gitconfig"))
+
+	t.Run("valid token", func(t *testing.T) {
+		server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			assert.Equal(t, "/api/v1/user", r.URL.Path)
+			assert.Equal(t, "token secret-token", r.Header.Get("Authorization"))
+			w.Header().Set("Content-Type", "application/json")
+			_, _ = w.Write([]byte(`{"id":1,"login":"alice"}`))
+		}))
+		defer server.Close()
+
+		status := CheckLoginStatus(context.Background(), &config.Login{
+			Name:         "test",
+			URL:          server.URL,
+			Token:        "secret-token",
+			VersionCheck: false,
+		})
+
+		assert.True(t, status.Valid)
+		assert.Empty(t, status.Error)
+		assert.Equal(t, "test", status.Name)
+		assert.Equal(t, server.URL, status.URL)
+		assert.Equal(t, "alice", status.User)
+		assert.Equal(t, "token", status.AuthMethod)
+		assert.False(t, status.Helper)
+	})
+
+	t.Run("invalid token", func(t *testing.T) {
+		server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusUnauthorized)
+			_, _ = w.Write([]byte(`{"message":"token is invalid"}`))
+		}))
+		defer server.Close()
+
+		status := CheckLoginStatus(context.Background(), &config.Login{
+			Name:         "test",
+			URL:          server.URL,
+			Token:        "expired-token",
+			VersionCheck: false,
+		})
+
+		assert.False(t, status.Valid)
+		assert.Contains(t, status.Error, "token is invalid")
+	})
+
+	t.Run("missing token", func(t *testing.T) {
+		status := CheckLoginStatus(context.Background(), &config.Login{
+			Name: "test",
+			URL:  "https://gitea.example.com",
+		})
+
+		assert.False(t, status.Valid)
+		assert.Contains(t, status.Error, "no access token configured")
+	})
+}