generate sourcemaps for code manipulations

[milahu]

ts-to-jsdoc uses ts-morph for code manipulations in typescript files

for example, ts-to-jsdoc adds jsdoc nodes:

/** Get JSDoc for a node or create one if there isn't any */
function getJsDocOrCreate(node: JSDocableNode): JSDoc {
  return node.getJsDocs()[0] || node.addJsDoc({});
}

addJsDoc calls insertIntoParentTextRange

/**
 * Inserts a text range into a parent.
 */
export function insertIntoParentTextRange(opts: InsertIntoParentTextRangeOptions) {
  const { insertPos, newText, parent } = opts;

  doManipulation(
    parent._sourceFile,
    new InsertionTextManipulator({
      insertPos,
      newText,
      replacingLength: opts.replacing?.textLength,
    }),
    new NodeHandlerFactory().getForParentRange({
      parent,
      start: insertPos,
      end: insertPos + newText.length,
      replacingLength: opts.replacing?.textLength,
      replacingNodes: opts.replacing?.nodes,
      customMappings: opts.customMappings,
    }),
  );
}

insertIntoParentTextRange calls InsertionTextManipulator

export class InsertionTextManipulator implements TextManipulator {
  constructor(private readonly opts: InsertionTextManipulatorOptions) {
  }

  getNewText(inputText: string) {
    const { insertPos, newText, replacingLength = 0 } = this.opts;
    return inputText.substring(0, insertPos) + newText + inputText.substring(insertPos + replacingLength);
  }

  getTextForError(newText: string) {
    return getTextForError(newText, this.opts.insertPos, this.opts.newText.length);
  }
}

... but the code manipulation is not recorded in a sourcemap

i am passing the option { sourceMap: true } to the typescript compiler
but this option is not used by ts-morph

    const project = new Project({
      compilerOptions: {
        target: ScriptTarget.ESNext,
        esModuleInterop: true,
        sourceMap: true,
        ...compilerOptions,
      },
    });

expected behavior: similar to https://github.com/Rich-Harris/magic-string

related downstream issue: futurGH/ts-to-jsdoc#19