API docs: codeintel: add OOB migration to index API docs for search
Created by: slimsag
This adds an OOB migration which will begin indexing historical LSIF uploads for API docs
search by pulling bundle data from the lsif_data_documentation_pages
table and writing
it to the new lsif_data_documentation_search_*
tables.
This is a one-time operation and, after a few Sourcegraph versions, this OOB migration will
be removed (as well as the temporary search_indexed
column on lsif_data_documentation_pages
which already exists).
See #25720 for more background
Helps #25193
Signed-off-by: Stephen Gutekanst [email protected]
Note: This PR was originally sent, reviewed partially, and merged in #25207 - but merged prematurely due to me fumbling communication with my reviewer, so I reverted in #25715 and am re-sending now.