Proposal: Add Contains filter when using QueryStateAsync

[edmondbaloku]

From the documentation it looks like there is no contains filter which would come in very handy if it was support for it.

I would like my frontend to be able to filter the mongodb by using a contains filter so that you don't always need to write the entire string and use the eq filter, this comes in handy when there is a search bar in the frontend and the user starts typing a string which we then could use to filter the database with a contains filter.

ref documentation: How-To: Query state

[WhitWaldo]

The query capability is perpetually stalled and not receiving updates at this time, as far as I'm aware.

[philliphoff]

Will close this as it's a Dapr state store wide concern and not specific to the .NET SDK.