Reduce Docker image sizes with multi-stage builds

[chicoferreira]

Related to #1

Implements multi-stage builds in Dockerfiles for homekit-mqtt-bridge and yeelight-controller to reduce image sizes.

• Introduces a builder stage using rust:1.72 for compiling the Rust applications in both Dockerfiles.
• Adds a runtime stage using debian:buster-slim to create lighter final images.
• Copies the compiled executables from the builder stage to the runtime stage, ensuring only necessary binaries and dependencies are included in the final images.
• Updates the CMD instruction to execute the copied binaries from their new location in /usr/local/bin/.

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