feat: Add Standard Schema support for Zod/Valibot/ArkType collection definitions

[CaptnClaw]

Summary

This PR adds support for defining collections using Standard Schema-compatible libraries (Zod, Valibot, ArkType) instead of the built-in field builders.

What's New

Core Features

• fromStandardSchema() - Low-level factory accepting any StandardSchemaV1 compliant schema
• fromZod() - Convenience wrapper that extracts Zod defaults automatically
• Type inference - Full TypeScript type inference from schemas via InferStandardSchema<T>
• Runtime validation - Schemas validate data on insert/update with detailed error messages

Collection Options

All existing collection features work with Standard Schema collections:

• publicId - Auto-generated public IDs with custom prefixes
• softDelete - Soft delete with deleted/deletedAt fields
• timestamps - Automatic createdAt/updatedAt tracking

Example Usage

import { z } from 'zod';
import { mizzle, fromZod } from '@mizzle-dev/orm';

const userSchema = z.object({
  email: z.string().email(),
  name: z.string(),
  role: z.enum(['user', 'admin']).default('user'),
});

const users = fromZod('users', userSchema, {
  publicId: 'user',
  softDelete: true,
});

Testing

• Unit tests for all new modules (standard-schema.test.ts, from-zod.test.ts)
• Integration tests for validation on insert/update
• E2E tests covering full workflow with publicId, softDelete, and timestamps
• All existing tests pass (backward compatibility verified)

Documentation

• Comprehensive README section with usage examples
• Migration guide for converting field builder definitions to Standard Schema
• Full working example in examples/standard-schema-zod.ts

Backward Compatibility

This is a purely additive feature. Existing field builder API remains unchanged and fully supported.