inject the backend query type map for pluggable backend selection

[kroepke]

Description

always also bind backends in the generic map binder, even for versioned backends in non-versioned backends, use the map binder directly so the engine can pick the correct backend based on the BackendQuery instance used

for query normalization, ignore non-elasticsearch based queries for now, we will need to address normalizers later to make them type safe (or just live with the instanceof check)

Simplified version of #21073

/nocl

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would cause existing functionality to change)

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