fix(sdk): make forceEmbedLayout default to true for embed methods

[fvsch]

A couple more updates for the upcoming 1.7.0 release.

Breaking-ish change

When using one of the StackBlitzSDK.embedProject* methods to generate a <iframe> embedding a StackBlitz project, and when the user doesn't provide a forceEmbedLayout value in EmbedOptions, then we set forceEmbedLayout to true instead of undefined.

This results in generated URLs having the embed=1 query string parameter and using the embed layout, instead of using the generic editor layout (with a top bar, login button, forking on saving as an anonymous user, etc.).

According to @EricSimons, the current behavior is a bug dating back 4+ years ago. So a fix would be welcome to make it more likely that embeds actually use the embed layout.

It's still a change in behavior, and while many users might see it as a feature upgrade, others might be relying on embedding the StackBlitz editor with the normal (non-embed) layout, which is kinda unsupported and can behave strangely but who knows, there might be a few people out there that make it work.

For those users of the SDK, their options would be remaining on @stackblitz/[email protected] or lower, or providing { forceEmbedLayout: false } in options.

Example usage:

// Default, embed layout
sdk.embedProjectId('sb-embed', 'my-cool-project', {
  openFile: 'src/main.ts',
});

// Or opt out of the embed layout (not officially supported!)
sdk.embedProjectId('sb-embed', 'my-cool-project', {
  forceEmbedLayout: true,
  openFile: 'src/main.ts',
});

A couple extra fixes for the road

• Encode file names in file= query string parameter
• Improve error message when not finding a target element id

[ggdaltoso]

Very good! 👌