fix: switch backend to CommonJS, generate Drizzle migrations, add migrate script

- Remove "type": "module" and switch tsconfig to CommonJS/Node resolution
  to fix drizzle-kit ESM/CJS incompatibility
- Strip .js extensions from all backend TypeScript imports
- Fix gamification resolver: combine two .where() calls using and()
- Fix index.ts: wrap top-level awaits in async main(), fix Fastify+yoga
  request handling via handleNodeRequestAndResponse
- Generate initial Drizzle SQL migration (0000_pale_hellion.sql) for all
  15 tables
- Add src/scripts/migrate.ts: programmatic Drizzle migrator for production
- Copy migrations folder into Docker image (Dockerfile.backend)
- Add schema:migrate npm script

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/backend/src/db/schema/articles.ts

@@ -6,8 +6,8 @@ import {
   index,
   uniqueIndex,
 } from "drizzle-orm/pg-core";
-import { users } from "./users.js";
-import { files } from "./files.js";
+import { users } from "./users";
+import { files } from "./files";
 
 export const articles = pgTable(
   "articles",

packages/backend/src/db/schema/comments.ts

@@ -5,7 +5,7 @@ import {
   index,
   integer,
 } from "drizzle-orm/pg-core";
-import { users } from "./users.js";
+import { users } from "./users";
 
 export const comments = pgTable(
   "comments",

packages/backend/src/db/schema/gamification.ts

@@ -8,8 +8,8 @@ import {
   pgEnum,
   uniqueIndex,
 } from "drizzle-orm/pg-core";
-import { users } from "./users.js";
-import { recordings } from "./recordings.js";
+import { users } from "./users";
+import { recordings } from "./recordings";
 
 export const achievementStatusEnum = pgEnum("achievement_status", [
   "draft",

packages/backend/src/db/schema/index.ts

@@ -1,7 +1,7 @@
-export * from "./files.js";
-export * from "./users.js";
-export * from "./videos.js";
-export * from "./articles.js";
-export * from "./recordings.js";
-export * from "./comments.js";
-export * from "./gamification.js";
+export * from "./files";
+export * from "./users";
+export * from "./videos";
+export * from "./articles";
+export * from "./recordings";
+export * from "./comments";
+export * from "./gamification";

packages/backend/src/db/schema/recordings.ts

@@ -9,8 +9,8 @@ import {
   uniqueIndex,
   jsonb,
 } from "drizzle-orm/pg-core";
-import { users } from "./users.js";
-import { videos } from "./videos.js";
+import { users } from "./users";
+import { videos } from "./videos";
 
 export const recordingStatusEnum = pgEnum("recording_status", [
   "draft",

packages/backend/src/db/schema/users.ts

@@ -8,7 +8,7 @@ import {
   uniqueIndex,
   integer,
 } from "drizzle-orm/pg-core";
-import { files } from "./files.js";
+import { files } from "./files";
 
 export const roleEnum = pgEnum("user_role", ["model", "viewer", "admin"]);
 

packages/backend/src/db/schema/videos.ts

@@ -8,8 +8,8 @@ import {
   uniqueIndex,
   primaryKey,
 } from "drizzle-orm/pg-core";
-import { users } from "./users.js";
-import { files } from "./files.js";
+import { users } from "./users";
+import { files } from "./files";
 
 export const videos = pgTable(
   "videos",