feat: initialize Next.js project with database schema

- Set up Next.js with App Router, TypeScript, Tailwind CSS
- Configure shadcn/ui with dark theme
- Install dependencies: lightweight-charts, papaparse, lucide-react
- Set up Drizzle ORM with better-sqlite3
- Create database schema for candles and annotations tables
- Generate migration SQL

src/lib/db/schema.ts

@@ -0,0 +1,18 @@
+import { sqliteTable, integer, real, text } from 'drizzle-orm/sqlite-core';
+
+export const candles = sqliteTable('candles', {
+  id: integer('id').primaryKey({ autoIncrement: true }),
+  time: integer('time').notNull().unique(),
+  open: real('open').notNull(),
+  high: real('high').notNull(),
+  low: real('low').notNull(),
+  close: real('close').notNull(),
+});
+
+export const annotations = sqliteTable('annotations', {
+  id: integer('id').primaryKey({ autoIncrement: true }),
+  timestamp: integer('timestamp').notNull(),
+  label_type: text('label_type').notNull(),
+  geometry: text('geometry'), // JSON string for line coordinates
+  created_at: integer('created_at').notNull(),
+});