doc: esm resolver spec refactoring for deprecations

[guybedford]

This PR integrates the current ES module resolver deprecations into the specification assuming those deprecations have all been runtime deprecated.

Specifically:

1. Removes the reference to the CJS module resolver when there is no "exports" field. This assumes the runtime deprecation of the index lookups deprecation, such that the main can just be resolved directly as a subpath without any statting when the exports fields is not declared by a package.
2. Since we now have trailing slash deprecations in patterns module: runtime deprecate trailing slash patterns #40117 as well as former folder deprecations for trailing slashes as well, when combined with (1) above the result is that trailing slashes never ever resolve for packages. As such when all of the above become runtime deprecations, it is possible to instead throw early as a resolution failure for package resolutions with a trailing slash. The refactoring is made now in the spec to indicate this, even though these runtime deprecations haven't happened yet. The goal being to ensure that the current spec reflects the current state with all deprecations enabled.

In the process I also spotted two simple spec editorial changes included here as well.

@nodejs/modules

Refs: #37206
Refs: #40117

[aduh95]

Could you add the refs to the PR that added the runtime deprecations please? That would help reviewing this. Also we should probably add dont-land labels as I think those deprecations haven't land on LTS release lines.

[guybedford]

@aduh95 the one reference is in the description, the other reference is the PR you did for the index deprecations I believe, is that the one you are after?

[aduh95]

Thanks for reminding me, I've added Refs: to the OP so it's added to the commit message on landing.

[guybedford]

Landed in ccee352.