feat: 增加友链申请、独立页面、投票/悬赏/抽奖帖与侧栏签到，并统一开发数据目录

Co-authored-by: Cursor <cursoragent@cursor.com>

service/post_special.go

@@ -0,0 +1,69 @@
+package service
+
+import (
+	"errors"
+	"strconv"
+
+	"git.iioio.com/freefire/jiang13-forum/model"
+	"gorm.io/gorm"
+)
+
+// PostCreateExtras 特殊帖创建附加参数
+type PostCreateExtras struct {
+	PollOptionsJSON    string
+	BountyPoints       int
+	LotteryWinnerCount int
+}
+
+// FinalizeSpecialPostCreate 创建帖后初始化投票/悬赏/抽奖
+func FinalizeSpecialPostCreate(post *model.Post, userID uint, extras PostCreateExtras) error {
+	if post == nil {
+		return errors.New("帖子不存在")
+	}
+	return model.DB.Transaction(func(tx *gorm.DB) error {
+		switch post.PostType {
+		case model.PostTypePoll:
+			opts, multi, maxChoices, endsAt, err := ParsePollOptionsJSON(extras.PollOptionsJSON)
+			if err != nil {
+				return err
+			}
+			return CreatePollForPost(tx, post.ID, multi, maxChoices, endsAt, opts)
+		case model.PostTypeBounty:
+			if extras.BountyPoints < 1 {
+				return ErrBountyInvalidPoint
+			}
+			if err := tx.Model(post).Updates(map[string]interface{}{
+				"bounty_points": extras.BountyPoints,
+				"bounty_status": model.BountyStatusOpen,
+			}).Error; err != nil {
+				return err
+			}
+			return EscrowBounty(tx, userID, post.ID, extras.BountyPoints)
+		case model.PostTypeLottery:
+			count := extras.LotteryWinnerCount
+			if count < 1 {
+				count = 1
+			}
+			if count > 20 {
+				return errors.New("开奖人数最多 20")
+			}
+			return tx.Model(post).Updates(map[string]interface{}{
+				"lottery_winner_count": count,
+				"lottery_status":       model.PostLotteryStatusOpen,
+			}).Error
+		default:
+			return nil
+		}
+	})
+}
+
+// ParsePostExtrasFromForm 从表单解析特殊帖参数
+func ParsePostExtrasFromForm(pollJSON, bountyRaw, lotteryRaw string) PostCreateExtras {
+	bounty, _ := strconv.Atoi(bountyRaw)
+	lottery, _ := strconv.Atoi(lotteryRaw)
+	return PostCreateExtras{
+		PollOptionsJSON:    pollJSON,
+		BountyPoints:       bounty,
+		LotteryWinnerCount: lottery,
+	}
+}