test(cli): add prismaSchemaFolder-specific tests

[jkomyno]

WIP

This PR closes https://github.com/prisma/team-orm/issues/1137.
It adds test cases to:

• packages/cli
  • validate
  • format
  • generate
• packages/internals
  • getDmmf
  • getConfig
  • getSchema

This PR also adds a new tree() utility to jestContext, which provides a JavaScript-friendly implementation of the tree UNIX command. It returns a string showcasing the file and directory structure starting from the fixture root directory:

import { jestContext } from '@prisma/get-platform'

const ctx = jestContext.new().assemble()

describe('validate', () => {
  it('some test using fixtures with many files and folders', () => {
    ctx.fixture('multi-schema-files/valid')
    expect(ctx.tree()).toMatchInlineSnapshot(`
      "
      └── prisma/
          └── schema/
              └── schema1.prisma
              └── schema2.prisma
          └── custom.prisma
          └── schema.prisma
      └── custom.prisma
      └── schema.prisma
      "
    `)
  })
})

The prismaSchemaFolder preview feature, which allows reading multiple schema files at once and combine them as a single schema, heavily relies on the file disk structure. This ctx.tree() utility allows to snapshot the disk structure in the tests, allowing easy future reference for Prisma developers.

[github-actions]

size-limit report 📦

Path	Size
packages/client/runtime/library.js	179.77 KB (0%)
packages/client/runtime/library.d.ts	81 B (0%)
packages/client/runtime/binary.js	600.89 KB (0%)
packages/client/runtime/binary.d.ts	26 B (0%)
packages/client/runtime/edge.js	159.02 KB (0%)
packages/client/runtime/edge-esm.js	158.91 KB (0%)
packages/client/runtime/wasm.js	114.85 KB (0%)
packages/client/runtime/index-browser.js	33.77 KB (0%)
packages/client/runtime/index-browser.d.ts	89 B (0%)
packages/cli/build/index.js	2.09 MB (+0.01% 🔺)
packages/client/prisma-client-0.0.0.tgz	3.02 MB (0%)
packages/cli/prisma-0.0.0.tgz	3.74 MB (+0.01% 🔺)
packages/bundle-size/da-workers-libsql/output.tgz	888.14 KB (0%)
packages/bundle-size/da-workers-neon/output.tgz	966.74 KB (0%)
packages/bundle-size/da-workers-pg/output.tgz	985.47 KB (0%)
packages/bundle-size/da-workers-pg-worker/output.tgz	941.18 KB (0%)
packages/bundle-size/da-workers-planetscale/output.tgz	903.56 KB (0%)
packages/bundle-size/da-workers-d1/output.tgz	861.2 KB (0%)

[codspeed-hq]

CodSpeed Performance Report

Merging #24141 will improve performances by 23.7%

_{Comparing feat/test-prismaSchemaFolder (8130b96) with main (23aba0b)}

Summary

⚡ 1 improvements
✅ 2 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	feat/test-prismaSchemaFolder	Change
⚡	client generation 100 models with relations	40.7 s	32.9 s	+23.7%