Decide the future of legacy SETU administration endpoints

[jenul-ferdinand]

What

Decide whether to build v2 SETU administration routes or remove unused v1 SETU list, aggregate, season, and write endpoints.

Why

No caller uses these v1 endpoints and no v2 replacement exists.

Area

• backend

Parent tracking issue

• [Parent] Convert the remaining v1 endpoints to v2 #208 Convert the remaining v1 endpoints to v2

Notes or constraints

• Separate public SETU unit reads from administration behaviour.
• Build v2 routes only for confirmed product or operational workflows.
• Delete unused v1 routes and tests.

Done when

• Each legacy SETU administration endpoint has a retained v2 path or is deleted.