FIX: #131 (query: "and" in subproperties)

Summary

Fix for https://gitlab.com/caosdb/caosdb-server/-/issues/131

See also #214 (closed)

Focus

The bug consisted of two problems:

1. In queries similar to FIND ENTITY WITH pname1.x>0 AND ... the part after the AND was interpreted as filters on pname1, not on the entity.
2. In queries similar to FIND ENTITY WITH ( pname1.x>0 ) AND ( ... ) everything after the first round bracket until the last round bracket was interpreted as the unit (so the unit was ) AND ( ...) and the query had only a single filter and the AND was not interpreted as a marker for the conjunction.

Test Environment

No special setup required.

Check List for the Author

• All automated tests pass
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