deployment: make gcpPodMonitoring enable configurable

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• deployment: make gcpPodMonitoring enable configurable #14240 👈 (View in Graphite)
• deployment: fix storage reader port #14229
• deployment: add service ports to hybrid common service overlays #14215
• deployment: extract common env to hybrid/common/common.yaml #14249
• deployment: extract core common config #14248
• deployment: extract mempool common config #14247
• deployment: extract gateway common config #14246
• deployment: extract l1 common config #14245
• deployment: extract committer common config #14244
• deployment: extract sierra-compiler common config #14243
• deployment: support include directive in common yaml loader #14242
• deployment: add gcp pod monitoring to hybrid environment overlays #14192 : 1 other dependent PR (#14196 )
• deployment: add liveness probe to hybrid environment overlays #14191
• deployment: add readiness probe to hybrid environment overlays #14190
• deployment: add startup probe to hybrid environment overlays #14188
• deployment: add monitoring endpoint port to hybrid environment overlays #14187
• main-v0.14.3

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PR Summary

Low Risk
YAML-only change to observability defaults; main operational risk is unintended PodMonitoring CR creation if missing enabled is treated as true elsewhere—worth confirming renderer defaults before rollout.

Overview
Removes the hardcoded gcpPodMonitoring.enabled: false entry from all six hybrid sequencer service layout files (committer, core, gateway, l1, mempool, sierra-compiler). Each file still documents scrape spec (port 8082, /monitoring/metrics, etc.); only the per-service “always off” flag is dropped.

That matches the deployment docs pattern where gcpPodMonitoring.enabled is the switch for creating GCP PodMonitoring CRs, so hybrid services are no longer forced disabled at the preset layer and enablement can be controlled via overrides or environment-specific values (as in the consolidated layout, which still shows enabled: false explicitly).

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