As discussed in bug#74610, in multi-language modes
treesit-outline-predicate ends abruptly after the first embedded range
since it can't find more matches in its range, it can't go out back
to the primary parser.

So this patch helps 'treesit-outline-search' to get out of the local parser
to the primary parser to continue search for the next outline predicate.

'treesit-outline-level' should do the same, but currently I can't find
a suitable function to break out of embedded confinement
and get the host node that contains the guest ranges.
I mean that e.g. (treesit-parser-root-node (treesit-node-parser node))
can get the root node of the local parser, but how to get its parent node
in the primary parser?  It's understandable that treesit-node-parent
doesn't go out of its parser.  But maybe there is another function?
If such function doesn't exist, this is fine, then could find that
node manually by calculating from treesit-parser-included-ranges.