fix: show the vault group number instead of the description on the el…

[anettkva]

Show the vault group number on the element page

Closes #125

For a vault, the element page showed the name of its element group under "Element group". For vaults that name is a long description (for example "Handspring, Yamashita, round-off with or without turn in 1st and/or 2nd flight phase"), not a short group name. The Elements list (#114) already shows "Group N" for a vault, so the element page now does the same, with the same rule.

Changes

• src/lib/catalogOperations.ts: the catalogItem query also asks for elementGroup { id number }. The id lets Apollo's cache recognise the same group across queries, which removes this query's part of the "Cache data may be lost when replacing the elementGroup field" warning.
• src/lib/catalog.ts: ElementDetail has elementGroupNumber, set by toElementDetail.
• src/lib/elementList.ts: groupLabel accepts anything with isVault, elementGroupName and elementGroupNumber, so the list and the element page use the same function. The rule itself is unchanged.
• src/components/elements/ElementMetadataCard.tsx: "Element group" shows groupLabel(element): "Group N" for a vault, and the name of the group for an element. (Prettier also reformatted two lines of the ElementValueBadge in this file.)
• docs/AI_USAGE.md: a new entry for this issue.

	Before	After
Vault 1.00	Element group: Handspring, Yamashita, round-off with or without turn in 1st and/or 2nd flight phase	Element group: Group 1
UB-1.101-a	Element group: Mounts	Element group: Mounts

Testing

• New tests in ElementDetailPage.test.tsx: one for an element (shows the name of the group) and one for a vault (shows "Group 1" and not the description), with the real group of VT-1.22-a. Each fails on its own when the page shows the name for every item or "Group N" for every item.
• catalog.test.ts checks that toElementDetail carries the number along.
• tsc -b, ESLint, Prettier (on the changed files), npm run build and all 202 frontend tests pass.
• Checked in a browser against the real backend: vault 1.00 shows "Group 1" in both the list and the element page, UB-1.101-a still shows "Mounts", and there is no Apollo warning in the console.

Not in this PR

• The Elements list query (searchOperations.ts) still asks for elementGroup without id, so the cache warning can still appear from the list.

🤖 Generated with Claude Code

[ronjalh]

lgtm