Expose macros config in babel

[NullVoxPopuli]

@embroider/macros were not configurable in main/vite before this change.

Proposed way of configuring macros is similar to how we've been doing so in ember-cli-build.js

For example, in the babel config:

const {
  babelCompatSupport,
  templateCompatSupport,
} = require("@embroider/compat/babel");

module.exports = {
  plugins: [
   // ... 
    ...babelCompatSupport({
      '@embroider/macros': {
        setOwnConfig: {},
        setConfig: {
          'library-name': {}
        },
      }
    }),
  ],
  // ...
};

However, this doesn't solve the problem of configuring macros for the minimal app over in #2205

For the minimal app blueprint, we'd have folks do this in their babel config:

const {
  babelCompatSupport,
  templateCompatSupport,
} = require("@embroider/compat/babel");

const { MacrosConfig } = require('@embroider/macros/src/macros-config');

let root = process.cwd();
let macros = MacrosConfig.for({}, root);
let { plugins: templateMacros, setConfig } = MacrosConfig.transforms();

setConfig(macros);

macros.setOwnConfig(root, { /* ... */ });
macros.setConfig(root, 'library-a', { /* ... */ });
macros.setConfig(root, 'library-b', { /* ... */ });

if (process.env.NODE_ENV === 'development') {
  macros.enablePackageDevelopment(process.cwd());
  macros.enableRuntimeMode();
}

macros.finalize();


module.exports = {
  plugins: [
    [
      "babel-plugin-ember-template-compilation",
      {
        compilerPath: "ember-source/dist/ember-template-compiler.js",
        transforms: [...templateMacros],
      },
    ],

   // ... 
   macros.babelPluginConfig();
  ],
  // ...
};

which.... could be better...

So.... I've done added to macros to allow for:

const { buildMacros } = require('@embroider/macros/babel'); 

const macros = buildMacros({
  // this is how you configure your own package
  setOwnConfig: {
    // your config goes here
  },
  // this is how you can optionally send configuration into your
  // dependencies, if those dependencies choose to use
  // @embroider/macros configs.
  setConfig: {
    'some-dependency': {
      // config for some-dependency
    },
  },
});

module.exports = {
  plugins: [
   // ... 
    [
      "babel-plugin-ember-template-compilation",
      {
        compilerPath: "ember-source/dist/ember-template-compiler.js",
        transforms: [...macros.templateMacros],
      },
    ],
    ...macros.babelMacros,
  ],
  // ...
};

Which should be nice for the minimal blueprint in #2205