Ship persistence in the default Amber V2 web app

[crimson-knight]

Summary

• make SQLite and Grant the supported default web-app persistence stack
• embed Micrate database operations in the compiled CLI
• generate working models, migrations, CRUD scaffolds, routes, ECR forms, and exact project-path guidance
• add Linux ARM64 and Windows generated-app gates and pin all release dependencies
• prepare CLI 2.0.4 for Amber 2.0.0-beta.3

Validation

• 407 CLI examples pass locally
• generated-app acceptance test passes: generate, migrate dev/test, 12 app specs, build, boot, create Pet, edit Pet, read it back
• beta contract passes

Coordination

• depends on Parse browser form data in schema controllers amber#1404
• depends on Support Amber V2 scaffold forms crimson-knight/grant#44
• depends on Prepare Micrate for Amber V2 persistence micrate#96
• CI temporarily checks the exact reviewed framework commit until beta.3 is tagged