Configure local_bridge_mtu network in docker-compose

[vaclav-ssvlabs]

Added local_bridge_mtu network configuration to services.

[Copilot]

Pull Request Overview

Adds a custom user-defined bridge network with a reduced MTU and attaches services to it to standardize container networking.

• Introduces a local_bridge_mtu network with MTU set to 1420.
• Connects postgres, sync, and calc services to the new network.

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[Copilot]

[nitpick] driver_opts values are expected as strings in Compose; quote the MTU to avoid type coercion issues across different Compose implementations.

Suggested change

	com.docker.network.driver.mtu: 1420
	com.docker.network.driver.mtu: "1420"

[Copilot]

[nitpick] Since all services are attached to the same network solely to apply the MTU, consider configuring the default network instead. This eliminates duplication and automatically applies to all services. Example: replace the bottom block with a 'default' network and remove the per-service 'networks' entries shown above.

[Copilot]

[nitpick] Since all services are attached to the same network solely to apply the MTU, consider configuring the default network instead. This eliminates duplication and automatically applies to all services. Example: replace the bottom block with a 'default' network and remove the per-service 'networks' entries shown above.

[Copilot]

[nitpick] Since all services are attached to the same network solely to apply the MTU, consider configuring the default network instead. This eliminates duplication and automatically applies to all services. Example: replace the bottom block with a 'default' network and remove the per-service 'networks' entries shown above.