Allow paragraphs or lists in body, not a mix of them

[knocte]

Test that should pass (exit code 0):

This is a title

Foo bar baz.

Bar baz foo.

Test that should pass (exit code 0):

This is a title

- Foo bar baz.
- Bar baz foo.

Test that should pass (exit code 0):

This is a title

* Foo bar baz.
* Bar baz foo.

Test that should fail (exit code !== 0):

This is a title

Foo bar baz.
Bar baz foo.

[knocte]

This is actually tricky to implement because of these 2 edge cases (should be exitCode = 0):

This is a title

This is a paragraph that has two sentences, each fits in 1 line.
The 2nd sentence.

(See above how 1st line fits 64 chars, so 2nd sentence has to go in next line.)

Another edge case:

This is a title

This commit msg only has 1 paragraph.
FooBarBaz123456789012345678 is a word that is too long to fit in
the first line of the paragraph.

(First line has less than 64 chars, but next word of 2nd sentence doesn't fit.)

[knocte]

Update: after thinking about it a bit more, it looks like this idea would somehow overlap with this other idea I had for another rule:

conventions/commitlint.config.ts

Line 44 in 2bd08fa

// * Detect if paragraphs in body have been cropped too shortly (less than 64 chars), and suggest same auto-wrap command that body-soft-max-line-length suggests, since it unwraps and wraps (both).

So maybe we want the rule to be called proper-body-wrap.