build: add TypeScript configuration and generate declaration files

- Add tsconfig.json for TypeScript compilation with declaration and source map generation
- Generate .d.ts declaration files for all modules, services, controllers, and models
- Update package.json with NestJS dependencies and TypeScript development tools
- Include database files in the distribution output for persistence

dist/models/weight-log.model.d.ts

@@ -0,0 +1,11 @@
+import { Model } from 'sequelize-typescript';
+import { User } from './user.model';
+export declare class WeightLog extends Model {
+    UserId: number;
+    user: User;
+    date: Date;
+    weight_kg: number;
+    body_fat_percentage: number;
+    notes: string;
+    time: string;
+}