refactor(auth): modularize auth plugin with physical subpackages and decoupled services

backend/plugins/domain/auth/consts/cap.go

@@ -0,0 +1,52 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+// Package consts defines constants, keys, and TTL values for the auth domain plugin.
+package consts
+
+import "time"
+
+// CAP 默认参数
+const (
+	DefaultCapChallengeCount      = 1
+	DefaultCapChallengeSize       = 32
+	DefaultCapChallengeDifficulty = 4
+	DefaultCapChallengeTTL        = 10 * time.Minute
+	DefaultCapTokenTTL            = 20 * time.Minute
+
+	RedeemTokenIDLength  = 8  // 兑换 Token ID 字节长度
+	RedeemVerTokenLength = 15 // 兑换验证 Token 字节长度
+	TokenPartsCount      = 2  // 兑换 Token 由两部分组成 (id:token)
+	ValuePartsCount      = 2  // 存储值由 scope 和过期时间组成 (expNano|scope)
+)
+
+// CAP 动态配置键常量
+const (
+	ConfigKeyCapLoginEnabled        = "cap_login_enabled"
+	ConfigKeyCapChallengeCount      = "cap_challenge_count"
+	ConfigKeyCapChallengeSize       = "cap_challenge_size"
+	ConfigKeyCapChallengeDifficulty = "cap_challenge_difficulty"
+	ConfigKeyCapChallengeTTL        = "cap_challenge_ttl"
+	// ConfigKeyCapTokenTTL 验证码 Token 过期时间键
+	// #nosec G101
+	ConfigKeyCapTokenTTL = "cap_token_ttl"
+)
+
+// HTTP 响应错误文案
+const (
+	ErrCapTokenMissing          = "验证码验证失败，缺少验证码凭证" //nolint:gosec // error message constant
+	ErrCapTokenInvalidOrExpired = "验证码校验失败或已过期，请重试" //nolint:gosec // error message constant
+	ErrCapNotConfigured         = "captcha is not configured"
+	ErrChallengeGenerateFailed  = "生成验证难题失败，请稍后再试"
+	ErrInvalidRequestParams     = "无效的参数"
+	ErrSolutionVerifyFailed     = "校验验证解答失败，请稍后再试"
+)
+
+// Redeem 结果码，属于 redeem 响应 JSON 的对外契约取值，禁止改写取值
+const (
+	RedeemErrInvalidToken     = "invalid_token"
+	RedeemErrNonceStoreFailed = "nonce_store_error"
+	RedeemErrAlreadyRedeemed  = "already_redeemed"
+	RedeemErrSettingsLoad     = "settings_load_error"
+	RedeemErrTokenStoreFailed = "token_store_error" //nolint:gosec // error code constant
+)