Feature request: Group related cards by subtype in the card details relations panel

[msmajevicpal]

Summary

The Relations panel on the card details page gives a nice overview per relation section ("is used by Organization", "uses IT Component", …), but within each section the related cards are rendered as one flat list. For hub cards this doesn't scale. Proposal: add a second grouping level inside each relation section, grouping the related cards by their subtype.

Current behavior

A relation section lists all target cards flat, e.g. on an Application card:

is used by Organization (23)
  Comp Europe GmbH
  Comp Marine GmbH
  Comp North America, LLC
  Comp GmbH
  ... (19 more)

With 20+ entries the section becomes a wall of names — you can't tell business units from legal entities from teams without opening each card.

Proposed behavior

Group the entries by the related card's subtype, using the subtype labels and ordering already defined in the metamodel:

is used by Organization (23)
├─ Business Unit (4)
│    Unit 1
│    Unit 2
│    ...
├─ Department (7)
│    ...
└─ Team (12)
     ...

The same mechanism applies generically to every relation section, since subtypes are metamodel-driven. Another example that benefits immediately — an Application's "uses IT Component" section with a customized metamodel:

uses IT Component (21)
├─ Software (3)
├─ Environment (16)
└─ Add-on / Plugin (2)

Suggested UX details

• Subtype groups are collapsible, with a count badge per group.
• Cards with no subtype fall into a trailing "(no subtype)" group — this also gently surfaces data-quality gaps.

Why

• Hub cards (group-wide ERP, integration platforms, shared infrastructure) routinely accumulate dozens of relations of the same type; flat lists make the panel hard to scan exactly where it matters most.
• Subtype is the one classification that is always available, metamodel-driven, and consistent across installations — no new configuration needed.
• It rewards good subtype hygiene: the better your inventory is classified, the better the relations panel reads.

Implementation notes

• The relations payload (GET /cards/{id}/relations, also surfaced via the MCP get_card_relations tool) currently serializes source / target as { id, type, name } only. Adding subtype to that serializer would allow the grouping to be done purely client-side, with subtype labels resolved from the card-type metadata the frontend already loads.

[vincentmakes]

Good idea and implemented in v2.16.0 - with the following feature / logic: it groups automatically only when a section has >=8 related cards spanning >=2 subtypes : small lists stay flat so the UI never adds noise. A per-section toggle in the group header lets you force grouped/flat regardless.