build(docker): optimize multi-stage build for op-node and geth

[NanoMindExplorer]

Summary

This PR refactors the Dockerfile to provide a cleaner, safer, and more efficient build process for both op-node and geth.

Changes

• Split the Dockerfile into three distinct stages (op-node, geth, and final image)
• Added pipefail and set -e for better error detection during build
• Added explicit branch and commit validation for reproducible builds
• Reduced image size by combining RUN layers and removing apt cache
• Added metadata labels and fixed binary permissions
• Replaced CMD with ENTRYPOINT for proper signal handling under supervisord

Motivation

Improves image reproducibility, security, and build performance.
Makes future maintenance easier by isolating build stages and improving readability.

Testing

• Built successfully with Docker 24.0+
• Verified that both geth and op-node binaries run correctly inside container
• Supervisor starts and manages both processes as expected

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1