feat: re-add scheduled task nodeSelector with correct indentation

[fedemaleh]

Summary

Re-adds nodeSelector support for scheduled task (CronJob) scopes. This supersedes #196, which was reverted (#197) because it rendered invalid YAML and broke deployments:

CronJob in version "v1" cannot be handled as a CronJob: strict decoding error:
unknown field "spec.jobTemplate.spec.template.spec.kubernetes.io/arch"

Root cause of the original breakage

nodeSelector is a map, but its content was rendered at indent 10 — the same column as the nodeSelector: key. That made the map entries (e.g. kubernetes.io/arch: arm64) siblings of nodeSelector: under template.spec instead of children. The neighboring tolerations block uses the same indent 10 and works only because it is a sequence (- markers disambiguate nesting).

Fix

Render the nodeSelector map content at indent 12, two spaces deeper than its key (the k8s deployment template already follows this rule).

Verification

Rendered the full CronJob template with the real arm64 modifier; kubernetes.io/arch: arm64 now nests correctly under nodeSelector:.

Changes

• scheduled_task/deployment/templates/deployment.yaml.tpl: nodeSelector block at indent 12.
• CHANGELOG.md: re-added the [Unreleased] entry removed by the revert.