[INF-7570] startupProbe support for all deployments

[lukefoster11]

Add startup probe support in the chart for all deployments, addressing issues with both workflows-backend and agent-sandbox-controller slow startups

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge because no blocking failure remains.

No blocking failure remains.

Important Files Changed

Filename	Overview
charts/retool/templates/_helpers.tpl	Adds a shared conditional renderer supporting HTTP and TCP startup probes.
charts/retool/values.yaml	Enables startup probes by default and defines workload-specific endpoints and startup windows.
values.yaml	Mirrors the chart’s new public startup-probe defaults.
charts/retool/templates/_workers.tpl	Applies worker-specific startup probes through the shared worker template and health port.
charts/retool/templates/deployment_workflows.yaml	Adds the workflow-backend startup probe using its component-specific configuration.
charts/retool/templates/deployment_agent_sandbox.yaml	Adds startup protection to both the sandbox controller and proxy.
charts/retool/templates/deployment_backend.yaml	Replaces the backend’s inline startup-probe rendering with the shared helper.

_{Reviews (2): Last reviewed commit: "all deployments" | Re-trigger Greptile}

[lukefoster11]

@greptile review me again pls