Add deprecation notices on whole APIs

mentioned in merge request gitlab-org/cli!2065 (merged)

mentioned in merge request gitlab-org/terraform-provider-gitlab!2463 (closed)

mentioned in merge request gitlab-com/gl-infra/autolabels!42 (merged)

mentioned in merge request gitlab-com/gl-infra/platform/runway/runwayctl!937 (merged)

mentioned in merge request gitlab-org/release-tools!4112 (merged)

mentioned in merge request gitlab-com/content-sites/handbook-tools/hugolint!138 (merged)

mentioned in merge request gitlab-com/gl-infra/oncall-robot-assistant!79

mentioned in merge request fforster/gitlab-mcp!11 (merged)

mentioned in merge request gitlab-com/gl-infra/ringctl!292 (merged)

mentioned in merge request gitlab-org/container-registry!2255 (merged)

mentioned in merge request sue445/tanuki_reminder!235 (merged)

mentioned in merge request sue445/create-merge-request!119 (merged)

mentioned in merge request !2265 (merged)

mentioned in merge request bitfoode/grc!5