SearchThresholdValue is currently a hardcoded value, it's function is to specify when a search word is ignored when doing FullText search.

This is mainly relevant for SQL ("Legacy") search engine, Solr/Elastic have own more advance config for this.

Suggested sub tasks:

• Expose a SPI method to get total content count and change code to have SearchThresholdPercentage of for instance 60% (same default as legacy)
  • ^{SPI cache can premature optimize this underneath on any spi call only affecting one content item (and not tree) to use inc / dec functions if Stash driver implements IncDecInterface, however no drivers do this atm, so a later optimization opportunity}
• Add semantic config to configure SearchThresholdPercentage