pub enum TraitType {
    // 大赛表现类
    Clutch,         // 大赛型：季后赛/国际赛 condition +3
    SlowStarter,    // 慢热型：第1局 condition -2，第3+局 +2
    FastStarter,    // 快枪手：第1局 condition +2，第3+局 -1

    // 稳定性类
    Explosive,      // 爆发型：stability -15，能力上限 +5
    Consistent,     // 稳定型：stability +10，能力上限 -3

    // 心态类
    ComebackKing,   // 逆风王：落后时 condition +3
    Tilter,         // 顺风浪：领先 condition -2，落后 -3
    MentalFortress, // 心态大师：momentum ×0.5
    Fragile,        // 玻璃心：输了 momentum -2

    // 体能类
    Ironman,        // 铁人：无疲劳惩罚
    Volatile,       // 状态敏感：stability -10

    // 特殊类
    RisingStar,     // 新星：首个赛季 ability +3
    Veteran,        // 老将风范：30岁后 stability +15
    TeamLeader,     // 团队核心：队友 condition +1
}

pub struct TraitEngine;

impl TraitEngine {
    /// 计算单个特性的修正值
    pub fn calculate_trait_modifier(trait_type: TraitType, ctx: &TraitContext) -> TraitModifiers

    /// 计算多个特性的综合修正（含钳位）
    pub fn calculate_combined_modifiers(traits: &[TraitType], ctx: &TraitContext) -> TraitModifiers

    /// 应用修正到选手属性，返回 (ability, stability, condition, ability_ceiling)
    pub fn apply_modifiers(ability: u8, stability: u8, condition: i8, mods: &TraitModifiers) -> (u8, u8, i8, u8)

    /// 随机生成选手特性
    pub fn generate_random_traits(ability: u8, age: u8, rng: &mut impl Rng) -> Vec<TraitType>
}

pub struct TraitContext {
    pub tournament_type: String,  // 赛事类型
    pub is_playoff: bool,         // 季后赛
    pub is_international: bool,   // 国际赛
    pub game_number: u8,          // 当前第几局 (1-5)
    pub score_diff: i8,           // 比分差 (正=领先)
    pub age: u8,                  // 选手年龄
    pub is_first_season: bool,    // 首个赛季
    pub games_since_rest: u32,    // 连续比赛场次
}

pub struct TraitModifiers {
    pub ability_mod: i8,            // 能力修正 [-10, 10]
    pub stability_mod: i8,          // 稳定性修正 [-20, 20]
    pub condition_mod: i8,          // 状态修正 [-5, 5]
    pub momentum_multiplier: f64,   // momentum 系数 (默认 1.0)
    pub ability_ceiling_mod: i8,    // 能力上限修正 [-5, 10]
}

pub struct MatchPlayerInfo {
    pub ability: u8,
    pub stability: u8,
    pub condition: i8,
    pub age: u8,
    pub position: String,
    pub traits: Vec<TraitType>,
    pub is_first_season: bool,
}

pub struct MatchSimContext {
    pub is_playoff: bool,
    pub is_international: bool,
    pub tournament_type: String,
}

pub fn simulate_match_with_traits(
    &self,
    match_id: u64, tournament_id: u64, stage: &str,
    format: MatchFormat,
    home_team_id: u64, away_team_id: u64,
    home_players: &[MatchPlayerInfo],
    away_players: &[MatchPlayerInfo],
    sim_ctx: &MatchSimContext,
    meta_weights: &MetaWeights,
) -> MatchResult

fn calculate_trait_adjusted_power(
    &self,
    players: &[MatchPlayerInfo],
    game_number: u8,
    score_diff: i8,
    sim_ctx: &MatchSimContext,
    meta_weights: &MetaWeights,
    team_leader_bonus: bool,
) -> f64

基础属性 → TraitEngine::calculate_combined_modifiers
         → TraitEngine::apply_modifiers
         → TeamLeader 队友 condition +1
         → N(0, (100 - stability) / 10) 噪声
         → clamp [ability-15, ability_ceiling]
         → MetaEngine 位置加权 → team_power

CREATE TABLE player_traits (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    save_id TEXT NOT NULL,
    player_id INTEGER NOT NULL,
    trait_type TEXT NOT NULL,
    acquired_season INTEGER,
    created_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP,
    UNIQUE(save_id, player_id, trait_type)
);