enhancement/issue 1220 adopt NodeJS register API for custom loaders

[thescientist13]

Related Issue

resolves #1220

Documentation

1. Need to document new custom loaders API usage and NodeJS 20.10.0 as minimum version with JSON Import Attributes + register function support (not just 20.6.0) - document latest usage and minimum NodeJS version for custom loaders usage www.greenwoodjs.dev#158

      Error building up import map TypeError [ERR_IMPORT_ASSERTION_TYPE_MISSING]: Module "file:///Users/owenbuckley/Workspace/project-evergreen/greenwood/node_modules/lit/package.json" needs an import assertion of type "json"
        at new NodeError (node:internal/errors:405:5)
        at validateAssertions (node:internal/modules/esm/assert:94:15)
        at defaultLoad (node:internal/modules/esm/load:117:3)
        at ModuleLoader.load (node:internal/modules/esm/loader:388:13)
        at ModuleLoader.moduleProvider (node:internal/modules/esm/loader:270:56)
        at new ModuleJob (node:internal/modules/esm/module_job:65:26)
        at #createModuleJob (node:internal/modules/esm/loader:282:17)
        at ModuleLoader.getJobFromResolveResult (node:internal/modules/esm/loader:240:34)
        at ModuleLoader.getModuleJob (node:internal/modules/esm/loader:221:17)
        at async ModuleLoader.import (node:internal/modules/esm/loader:307:23) {
      code: 'ERR_IMPORT_ASSERTION_TYPE_MISSING'
      }
      

Summary of Changes

1. Create a register function and adopted for an export alias (and thus had to create an exports map for Greenwood as needed)

        node:internal/process/esm_loader:48
        internalBinding('errors').triggerUncaughtException(
                                  ^
      Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './src/lib/resource-utils.js' is not defined by "exports" in /Users/owenbuckley/Workspace/github/greenwood-lit-ssr/node_modules/.pnpm/@[email protected]_@[email protected]/node_modules/@greenwood/cli/package.json imported from /Users/owenbuckley/Workspace/github/greenwood-lit-ssr/node_modules/.pnpm/@[email protected]_@[email protected]/node_modules/@greenwood/plugin-adapter-vercel/src/index.js
      

2. Bump GitHub Actions to [20, 22] though seems we can keep engines at >=18.20.5 (overlaps with Upgrade to Node 20.x (latest LTS) #1202 )

Example repo - thescientist13/greenwood-lit-ssr#28

TODO

1. (right after merge) Update GitHub Actions version check(s)
2. (nice to have) self invoke greenwood w/ command

   import { register } from 'node:module';
   
   register('./loader.js', import.meta.url);
   
   // TODO can we do this for the user?
   // await import('./index.js');

3. (nice to have) can we clean up the invocation / no userland flag?

   "dev": "node --import @greenwood/cli/register ./node_modules/@greenwood/cli/src/index.js develop",