More efficient database management

[giocomai]

Cache less

• cache only requested properties
• enable pruning of properties: remove from the cache properties that are known to be unnecessary in a given project

Make cache more efficient

• Use separate tables for properties (all P[:digit:]+), with content that is language agnostic, and other fields, such as label, description, alias, wikipedia link, etc., that are language specific
• drop letter "P" from the property column, and turn the column into numeric type
• drop letter "Q" from id column, and turn into numeric type
• make sure new tables are created already indexed
• prepare function for updating the database when deprecating old tables

Easier support for multi-lingual contexts

• keep language-agnostic part of the properties in a separate property (see above)

Alternative backends

• check and compare SQLite and DuckDB speed in this context

Cache more quickly

• Interact directly with the API to get batches of up to 50 items #7