Add detailed migrations and TypeScript IDE comparison

Compare automatic migration generation and TypeScript IDE support
across all 4 ORMs:

Rankings:
- Best Migrations: Prisma > Drizzle > MikroORM > TypeORM
- Best TypeScript IDE Hints: Drizzle > Prisma > MikroORM > TypeORM

Key findings:
- Drizzle has best-in-class type inference with zero codegen
- Prisma has excellent types via codegen + smoothest migrations
- TypeORM has weakest type safety (strings not validated)
- MikroORM is solid middle ground

Recommendation: Drizzle for best types, Prisma for best overall DX

orm-comparison/MIGRATIONS_AND_TYPES.md

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+# Automatic Migrations & TypeScript IDE Support Comparison
+
+## Summary Table
+
+| ORM | Auto Migration Generation | TypeScript IDE Hints | Winner |
+|-----|--------------------------|---------------------|--------|
+| **Prisma** | ✅ Excellent | ✅ Excellent (codegen) | 🏆 Best DX |
+| **Drizzle** | ✅ Excellent | ✅ **BEST** (no codegen) | 🏆 Best Types |
+| **TypeORM** | ✅ Good | ⚠️ Limited | ❌ |
+| **MikroORM** | ✅ Very Good | ✅ Good | ✅ |
+
+---
+
+## Detailed Breakdown
+
+### 1️⃣ Prisma
+
+#### ✅ Automatic Migrations: EXCELLENT
+```bash
+# After changing schema.prisma:
+npx prisma migrate dev --name add_new_field
+# ✅ Automatically generates SQL migration
+# ✅ Applies migration to DB
+# ✅ Regenerates TypeScript client
+```
+
+**Pros:**
+- Declarative - just edit `.prisma` file
+- Generates clean SQL migrations
+- Handles complex schema changes well
+- Can review/edit SQL before applying
+
+**Cons:**
+- Requires separate schema file (not TypeScript)
+
+#### ✅ TypeScript IDE Hints: EXCELLENT
+```typescript
+import { PrismaClient } from '@prisma/client';
+const prisma = new PrismaClient();
+
+// 🎯 FULL autocomplete on everything:
+const user = await prisma.user.findUnique({
+  where: { id: 'some-uuid' },  // ← knows 'id' field exists
+  include: {
+    snapshots: true,            // ← knows this relation exists
+  },
+});
+
+// user.username    // ← IDE knows this is string
+// user.snapshots   // ← IDE knows this is Snapshot[]
+// user.notAField   // ← TypeScript ERROR at compile time
+```
+
+**Pros:**
+- Perfect autocomplete on all queries
+- Catches typos at compile time
+- Infers result types automatically
+- Works with any IDE (VSCode, WebStorm, etc.)
+
+**Cons:**
+- Requires running `npx prisma generate` after schema changes
+- Generated client can be large (~50MB in node_modules)
+
+---
+
+### 2️⃣ Drizzle
+
+#### ✅ Automatic Migrations: EXCELLENT
+```bash
+# After changing schema.drizzle.ts:
+npx drizzle-kit generate:pg
+# ✅ Automatically generates SQL migration files
+# ✅ You review them, then:
+npx drizzle-kit push:pg
+# ✅ Applies to database
+```
+
+**Pros:**
+- Schema IS TypeScript (no separate file)
+- Generates readable SQL migrations
+- Git-friendly migration files
+- Can edit generated SQL
+
+**Cons:**
+- Two-step process (generate → apply)
+
+#### ✅ TypeScript IDE Hints: **BEST-IN-CLASS**
+```typescript
+import { drizzle } from 'drizzle-orm/postgres-js';
+import { users, snapshots } from './schema.drizzle';
+
+const db = drizzle(connection);
+
+// 🎯 PERFECT autocomplete, NO codegen required:
+const user = await db
+  .select()
+  .from(users)
+  .where(eq(users.id, 'some-uuid'))
+  .leftJoin(snapshots, eq(snapshots.created_by_id, users.id));
+
+// Type is inferred as:
+// { users: typeof users.$inferSelect, snapshots: typeof snapshots.$inferSelect | null }[]
+
+// user[0].users.username     // ← string
+// user[0].snapshots?.url     // ← string | undefined
+// user[0].users.notAField    // ← TypeScript ERROR
+```
+
+**Pros:**
+- **Zero codegen** - types come from schema directly
+- Best type inference of all ORMs
+- Smallest bundle size
+- Schema changes = instant type updates
+- Autocomplete on table names, columns, relations
+
+**Cons:**
+- None for type safety (this is the gold standard)
+
+---
+
+### 3️⃣ TypeORM
+
+#### ✅ Automatic Migrations: GOOD
+```bash
+# After changing entity classes:
+npx typeorm migration:generate -n AddNewField
+# ✅ Generates migration by comparing entities to DB
+# ⚠️ Can be buggy with complex changes
+
+npx typeorm migration:run
+```
+
+**Pros:**
+- Can generate migrations from entity changes
+- Established tool
+
+**Cons:**
+- Auto-generation often needs manual fixes
+- Doesn't always detect all changes
+- Generated migrations can be messy
+- Many devs write migrations manually
+
+#### ⚠️ TypeScript IDE Hints: LIMITED
+```typescript
+import { User } from './entities/User';
+import { Repository } from 'typeorm';
+
+const userRepo: Repository<User> = connection.getRepository(User);
+
+// ⚠️ Autocomplete on entity properties only:
+const user = await userRepo.findOne({
+  where: { id: 'some-uuid' },  // ✅ knows 'id' exists
+  relations: ['snapshots'],    // ❌ 'snapshots' is just a string - no validation!
+});
+
+// user.username    // ✅ IDE knows this is string
+// user.snapshots   // ✅ IDE knows this is Snapshot[]
+// user.notAField   // ✅ TypeScript ERROR
+
+// BUT:
+const user2 = await userRepo
+  .createQueryBuilder('user')
+  .where('user.id = :id', { id: 'uuid' })  // ❌ 'id' is just a string - no validation!
+  .leftJoinAndSelect('user.snapshots', 's') // ❌ 'snapshots' not validated!
+  .getOne();
+// ⚠️ user2 type is just "User | null" - doesn't know snapshots are loaded
+```
+
+**Pros:**
+- Basic entity typing works
+- Better than no types
+
+**Cons:**
+- Query strings are not type-checked (huge DX issue)
+- Relation names in queries are strings (typos not caught)
+- QueryBuilder doesn't infer loaded relations
+- Worse type safety than Prisma or Drizzle
+
+---
+
+### 4️⃣ MikroORM
+
+#### ✅ Automatic Migrations: VERY GOOD
+```bash
+# After changing entity classes:
+npx mikro-orm schema:update --safe
+# ✅ Generates migration based on entity changes
+# ✅ Better detection than TypeORM
+```
+
+**Pros:**
+- Good auto-generation (better than TypeORM)
+- Smart detection of changes
+- Safe mode prevents destructive changes
+
+**Cons:**
+- Still occasionally needs manual tweaking
+
+#### ✅ TypeScript IDE Hints: GOOD
+```typescript
+import { User } from './entities/User';
+import { MikroORM } from '@mikro-orm/core';
+
+const orm = await MikroORM.init({ ... });
+const em = orm.em.fork();
+
+// ✅ Good autocomplete with better inference than TypeORM:
+const user = await em.findOne(User,
+  { id: 'some-uuid' },        // ✅ knows 'id' exists
+  { populate: ['snapshots'] } // ⚠️ Still a string, but has const validation
+);
+
+// user.username    // ✅ IDE knows this is string
+// user.snapshots   // ✅ IDE knows this is Collection<Snapshot>
+// user.notAField   // ✅ TypeScript ERROR
+
+const users = await em.find(User, {
+  username: { $like: '%test%' }  // ✅ knows 'username' exists
+});
+```
+
+**Pros:**
+- Much better than TypeORM
+- Strongly typed entities
+- Better QueryBuilder types
+- Type-safe filters
+
+**Cons:**
+- Not as good as Prisma's generated client
+- Not as good as Drizzle's inference
+- Some query methods still use strings
+
+---
+
+## 🏆 Rankings
+
+### Best Automatic Migrations
+1. **Prisma** - Smoothest experience, excellent detection
+2. **Drizzle** - Great SQL generation, transparent
+3. **MikroORM** - Very good detection
+4. **TypeORM** - Works but often needs manual fixes
+
+### Best TypeScript IDE Hints
+1. **Drizzle** 🥇 - Best type inference, zero codegen
+2. **Prisma** 🥈 - Perfect types via codegen
+3. **MikroORM** 🥉 - Good types, better than TypeORM
+4. **TypeORM** - Basic types, many strings not validated
+
+---
+
+## 💡 Recommendations
+
+### If you prioritize TypeScript IDE experience:
+**Choose Drizzle** - Best-in-class type inference without codegen
+
+### If you want the easiest developer experience overall:
+**Choose Prisma** - Great migrations + great types (via codegen)
+
+### If you need both features to work well:
+**Avoid TypeORM** - Weakest typing, especially in queries
+
+### Middle ground:
+**MikroORM** - Both features work well, not as polished as Prisma/Drizzle
+
+---
+
+## Code Examples Side-by-Side
+
+### Creating a new Snapshot with relations:
+
+#### Prisma
+```typescript
+const snapshot = await prisma.snapshot.create({
+  data: {
+    url: 'https://example.com',
+    timestamp: '1234567890',
+    created_by: { connect: { id: userId } },  // ← fully typed
+    crawl: { connect: { id: crawlId } },      // ← fully typed
+    tags: {
+      connect: [{ id: tag1Id }, { id: tag2Id }]  // ← fully typed
+    }
+  },
+  include: {
+    created_by: true,  // ← IDE knows this relation exists
+    tags: true,        // ← IDE knows this relation exists
+  }
+});
+// Result type automatically inferred with all included relations
+```
+
+#### Drizzle
+```typescript
+const [snapshot] = await db
+  .insert(snapshots)
+  .values({
+    url: 'https://example.com',
+    timestamp: '1234567890',
+    created_by_id: userId,   // ← fully typed
+    crawl_id: crawlId,       // ← fully typed
+  })
+  .returning();
+
+// For relations, need separate queries or joins:
+const snapshotWithRelations = await db
+  .select()
+  .from(snapshots)
+  .leftJoin(users, eq(snapshots.created_by_id, users.id))
+  .leftJoin(tags, eq(snapshot_tags.snapshot_id, snapshots.id))
+  .where(eq(snapshots.id, snapshot.id));
+// Type fully inferred: { snapshots: Snapshot, users: User | null, tags: Tag | null }
+```
+
+#### TypeORM
+```typescript
+const snapshot = snapshotRepo.create({
+  url: 'https://example.com',
+  timestamp: '1234567890',
+  created_by_id: userId,   // ⚠️ Manual FK handling
+  crawl_id: crawlId,       // ⚠️ Manual FK handling
+});
+await snapshotRepo.save(snapshot);
+
+// For relations, need separate loading:
+const loaded = await snapshotRepo.findOne({
+  where: { id: snapshot.id },
+  relations: ['created_by', 'tags'],  // ⚠️ strings not validated
+});
+```
+
+#### MikroORM
+```typescript
+const snapshot = em.create(Snapshot, {
+  url: 'https://example.com',
+  timestamp: '1234567890',
+  created_by: em.getReference(User, userId),  // ✅ typed reference
+  crawl: em.getReference(Crawl, crawlId),     // ✅ typed reference
+});
+await em.persistAndFlush(snapshot);
+
+// Relations auto-loaded with populate:
+const loaded = await em.findOne(Snapshot, snapshot.id, {
+  populate: ['created_by', 'tags'],  // ⚠️ still strings
+});
+```
+
+---
+
+## Final Verdict
+
+**For your use case (migrations + IDE hints):**
+
+🥇 **Drizzle** - Best types, great migrations, no codegen
+🥈 **Prisma** - Great at both, but requires codegen step
+🥉 **MikroORM** - Solid at both, more complex patterns
+❌ **TypeORM** - Weak typing in queries, avoid for new projects
+