feat: 添加数据模型和存储层

- model: JobTemplate、SubmitJobRequest、JobHistoryQuery 等模型定义

- store: NewGormDB MySQL 连接池，使用 zap 日志替代 GORM 默认日志

- store: TemplateStore CRUD 操作，支持 GORM AutoMigrate

- NewGormDB 接受 gormLevel 参数，由上层传入配置值

- 完整 TDD 测试覆盖

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

internal/store/migrations/001_create_job_templates.up.sql

@@ -0,0 +1,14 @@
+CREATE TABLE IF NOT EXISTS job_templates (
+    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
+    name VARCHAR(255) NOT NULL,
+    description TEXT,
+    script TEXT NOT NULL,
+    partition VARCHAR(255),
+    qos VARCHAR(255),
+    cpus INT UNSIGNED,
+    memory VARCHAR(50),
+    time_limit VARCHAR(50),
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    UNIQUE KEY idx_name (name)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;