Fix: When using the toolbox-search, auto select the found dropdown item

[constantinIliescu]

Fixes: https://github.com/google/blockly-samples/issues/1940

Uses the Block State as suggested here: https://github.com/google/blockly-samples/pull/2004#issuecomment-1832317907

Fixes: bug that didn't indexed the last trigram from a word

The basics

• [ x] I validated my changes

The details

Resolves

Fixes https://github.com/google/blockly-samples/issues/1940

Proposed Changes

Use block state for efficient indexing

Reason for Changes

Have the found drop down item automatically selected in the drop down

Test Coverage

Unit test have been added to cover the false positive, false negative and duplicate cases

Documentation

Additional Information