fix: add base-consensus binary to geth and nethermind Dockerfiles

[Sertug17]

Fixes #1016

reth/Dockerfile already includes the base-consensus binary, but geth/Dockerfile and nethermind/Dockerfile were missing it entirely.

Operators using geth or nethermind with USE_BASE_CONSENSUS=true would get "Base client is not supported for this node type" error and fail to start — potentially missing the April 20th Base V1 Sepolia upgrade deadline.

Changes:

• Added Rust builder stage to both Dockerfiles
• Added base-consensus binary copy from builder
• Added base-consensus-entrypoint copy

[cb-heimdall]

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