feat(spanner/spansql): Add support for tokenlist and create search index

[rasviitanen]

Adds support for parsing tokenlist and create search index in spanner/spansql.

Fixes #11466

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[rasviitanen]

Thanks for the review, I have now fixed your comments.
I expanded the tests a bit and also fixed some issues with ORDER BY and OPTIONS.

[neophenix]

Awesome thanks! I did not do an exhaustive review, these were just things I ran into when I pulled your branch and was running some local tests, but the changes all seem to work for me, so fingers crossed :)