[rfw] Add an example of using JavaScript with RFW

[moluopro]

I have added an example using JavaScript with RFW. This new example essentially replicates the functionality of the previous wasm example. Since the wasm package has been marked as discontinued and can no longer run directly on certain platforms, I included this new example as a replacement.

The new example is compatible with all Flutter platforms.

Pre-Review Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene page, which explains my responsibilities.
• I read and followed the relevant style guides and ran the auto-formatter.
• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or I have commented below to indicate which version change exemption this PR falls under¹.
• I updated CHANGELOG.md to add a description of the change, following repository CHANGELOG style, or I have commented below to indicate which CHANGELOG exemption this PR falls under¹.
• I updated/added any relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or I have commented below to indicate which test exemption this PR falls under¹.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

Footnotes

1. Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling. ↩ ↩² ↩³

[moluopro]

I believe the wasm case should be removed, as it often fails to run in the new version of Flutter. Since this is a significant change, I would like to get the reviewer's opinion. @stuartmorgan-g

[stuartmorgan-g]

@moluopro Please do not comment in completely unrelated PRs to request reviews. The proper escalation path, as explained in our contributor documentation, is to contact the reviewer via Discord.

I would like to get the reviewer's opinion. @stuartmorgan-g

The reviewer is @Hixie, the code owner for this package, not me.

[moluopro]

@moluopro Please do not comment in completely unrelated PRs to request reviews. The proper escalation path, as explained in our contributor documentation, is to contact the reviewer via Discord.

I would like to get the reviewer's opinion. @stuartmorgan-g

The reviewer is @Hixie, the code owner for this package, not me.

I’m really sorry! I saw in that PR that, since Hixie didn’t respond, he reached out to you, so I thought I could do the same. I’m not very familiar with this process, as this is my first time submitting a PR for this library. I apologize again for the inconvenience caused.

[Hixie]

It's an interesting example, but I don't really understand the use case for using RFW with a JS backend. If you're using JS, why not just send HTML?

[moluopro]

The main reason I want to submit this change is that the WASM example is not running. I believe it's important to ensure that the official examples work on all Flutter platforms.

Secondly, JavaScript is a popular language with many users, so I chose it as the case.