feat: support import.meta.ROLLUP_FILE_URL_(referenceId)

[hi-ogawa]

Description

Reviving #1928. I came across import.meta.url.ROLLUP_FILE_URL_xxx in one of my plugins (hi-ogawa/vite-plugins#673) and I think having the compat in rolldown is nice to have (though it's also possible to have a compat in rolldown-vite or user land level via a custom plugin's renderChunk replacing).

Sapphi also mentioned that Astro uses this feature #819 (comment). I'm hoping the complexity required on rolldown side is low and it's worth the inclusion. Let me know what you think.

Example user-land plugin to replace "import.meta.ROLLUP_FILE_URL_xxx"

From hi-ogawa/vite-plugins#673

import path from "node:path";
import MagicString from "magic-string";
import type { Plugin } from "vite";

// import.meta.ROLLUP_FILE_URL_xxx on rolldown
// https://github.com/rolldown/rolldown/pull/1928
export function rolldownPluginRollupFileUrl(): Plugin {
  return {
    name: rolldownPluginRollupFileUrl.name,
    renderChunk: {
      order: "pre",
      handler(code, chunk) {
        if (!code.includes("import.meta.ROLLUP_FILE_URL_")) {
          return;
        }
        const matches = code.matchAll(/import.meta.ROLLUP_FILE_URL_(\w+)/dg);
        const output = new MagicString(code);
        for (const match of matches) {
          const referenceId = match[1]!;
          const assetFileName = this.getFileName(referenceId);
          const relativePath =
            "./" +
            path.relative(
              path.resolve(chunk.fileName, ".."),
              path.resolve(assetFileName),
            );
          const replacement = `new URL(${JSON.stringify(relativePath)}, import.meta.url)`;
          const [start, end] = match.indices![0]!;
          output.update(start, end, replacement);
        }
        if (output.hasChanged()) {
          return {
            code: output.toString(),
            map: output.generateMap({ hires: "boundary" }),
          };
        }
        return;
      },
    },
  };
}

[IWANABETHATGUY]

We should either add SAFETY comments or expect instead of unwrap, attend to give a more friendly panic message.

[hi-ogawa]

Replaced unwrap with expect 👍
FYI, I referenced the code from Chunk::import_path_for, which computes relative chunk path. I'll try to refactor some repeated code separately later.

rolldown/crates/rolldown_common/src/chunk/mod.rs

Lines 88 to 92 in aad0c09

	pub fn import_path_for(&self, importee: &Chunk) -> String {
	let importer_dir =
	self.absolute_preliminary_filename.as_ref().unwrap().as_path().parent().unwrap();
	let importee_filename = importee.absolute_preliminary_filename.as_ref().unwrap();
	let import_path = importee_filename.relative(importer_dir).as_path().expect_to_slash();