Docs: 'project' index option is not documented

[dmeehan1968]

Describe the bug

According to the types for schema indexes, there is an index option 'project' which is either 'keys_only' or undefined. This is not documented in the Index Options table, nor elsewhere in the Indexes page.

ElectroDB Version

2.14.3

Expected behavior

'project' option should be documented.

[tywalch]

That property does not currently change library behavior