feat: add Jinshuju student sync

apps/server/src/entities/jinshuju-match-rule.entity.ts

@@ -0,0 +1,53 @@
+import { Entity, PrimaryGeneratedColumn, Column, CreateDateColumn, UpdateDateColumn } from 'typeorm';
+
+/**
+ * Field mappings from Jinshuju field keys (field_1, field_2, ...) to Student columns.
+ * Only mapped fields are extracted; unmapped fields are ignored.
+ */
+export interface JinshujuFieldMapping {
+  /** Jinshuju field key → Student column name */
+  name?: string;         // e.g. "field_1"
+  phone?: string;        // e.g. "field_2"
+  idNumber?: string;     // e.g. "field_3"
+  gender?: string;
+  ethnicity?: string;
+  emergencyContact?: string;
+  emergencyPhone?: string;
+  studentNo?: string;
+}
+
+export const DEFAULT_MAPPING: JinshujuFieldMapping = {
+  name: 'field_1',
+  phone: 'field_2',
+};
+
+const mappingTransformer = {
+  to(value: JinshujuFieldMapping): string {
+    return JSON.stringify(value);
+  },
+  from(value: string | null): JinshujuFieldMapping {
+    if (!value) return {};
+    return JSON.parse(value);
+  },
+};
+
+@Entity('jinshuju_match_rules')
+export class JinshujuMatchRule {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column({ length: 100 })
+  name: string;
+
+  @Column({ name: 'form_token', length: 64 })
+  formToken: string;
+
+  @Column({ type: 'text', transformer: mappingTransformer })
+  mappings: JinshujuFieldMapping;
+
+  @CreateDateColumn({ name: 'created_at' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at' })
+  updatedAt: Date;
+}