deployment: add readiness probe to hybrid environment overlays

[nimrod-starkware]

Cross-repo PR: https://github.com/starkware-industries/sequencer-devops/pull/715

Cross-repo PR: https://github.com/starkware-industries/sequencer-devops/pull/715

[reviewable-StarkWare]

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[nimrod-starkware]

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• deployment: define common env #14196
• deployment: add gcp pod monitoring to hybrid environment overlays #14192
• deployment: add liveness probe to hybrid environment overlays #14191
• deployment: add readiness probe to hybrid environment overlays #14190 👈 (View in Graphite)
• deployment: add startup probe to hybrid environment overlays #14188
• deployment: add monitoring endpoint port to hybrid environment overlays #14187
• deployment: add service ports to hybrid environment overlays #14185
• deployment: move network and consensus ports to hybrid environment overlays #14183
• deployment: add component ports and urls to hybrid environment overlays #14181
• deployment: add recorder_url to hybrid environment overlays #14180
• deployment: add starknet_url to hybrid environment overlays #14179
• main

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[cursor]

PR Summary

Medium Risk
Touches mainnet and live Sepolia hybrid rollout behavior (traffic during deploys); no app code changes, but mis-tuned readiness could delay or block rollouts.

Overview
Enables Kubernetes readiness checks for hybrid sequencer deployments on mainnet, sepolia-alpha, and sepolia-integration by adding the same readinessProbe block to each environment’s shared common.yaml overlay.

The new probe hits /monitoring/ready on the existing monitoring port (alongside the already-configured startup probe on /monitoring/alive), with successThreshold: 2, failureThreshold: 3, and 5s period/2s timeout. That aligns these production-like hybrid overlays with the probe settings already used in hybrid testing overlays.

Effect: pods are only marked ready (and included in Service endpoints during rollouts) once the sequencer reports ready via the monitoring endpoint, rather than relying on startup alone.

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