Before this commit searched terms were the ones entered by the end-user.
After this commit if the searched term is not found then the search is
performed on a resembling term.
The similarity is obtained from a Levenshtein distance combined with
ratios of common and different letters.
By default the dictionary against which the search term is matched is
based on the content of the search fields containing a word that starts
with the first letter of the search term.
If the `pg_trgm` Postgresql extension is installed the dictionary is
built from matches using the `<%%` operator (similar to the
`word_similarity` function).
Several approaches were benchmarked during development, those results
are available through the task record.
task-2379555
https://github.com/odoo/odoo/pull/65871
Part-of: odoo/odoo#65871
Benoit Socias
c6ba756e4b