rollup should respect the preset while reading package.json exports

[Hebilicious]

Motivation

When building for worker runtimes such as cloudflare/vercel-edge, there's an issue where the rollup plugin node resolve will follow the default priority which is good for Node, but not for these environments, which means in these scenarios many dependencies needs to be alias manually to their browser version.

Describe the feature

Depending on the preset, we should alter rollup node-resolve exportConditions order priority.

For example for Cloudflare like environments, we could try workerd > browser > import > default > module > deno > node.
For deno we could try deno > browser > import > default > workerd > module > node

It looks like there's a lot of edge cases and no convention defined, ie vercel uses edge-light, libsql use web and http ...
We could run into an issue where we don't have the correct export no matter how much we try, hence why we should give the ability to customise this through Nitro options, as well as document it.

https://github.com/rollup/plugins/blob/master/packages/node-resolve/README.md
https://github.com/unjs/nitro/blob/main/src/rollup/config.ts

Edit : There's some convention defined there https://runtime-keys.proposal.wintercg.org/ , but no guarantee that libraries authors respect it.

Additional information

• Would you be willing to help implement this feature?

[pi0]

Related:

• Allow exported export conditions: Allow extending export conditions #83
• Using web export condition for Worker presets: prefer web over node export condition for non-node targets #1123
• Adoption for runtime-keys: feat(pkg): add export conditions for runtime keys unjs/node-fetch-native#75 (we probably need to prefer this over for worker preset conditions)

[Hebilicious]

Reference for bun https://github.com/unjs/nitro/pull/1313/files#diff-796b6929127793d228570ad4369ba444daa8aab71f8376996bb5be24cf0a18fb