Teams PR 1 — data-farm store + first consumer

[n-lark]

PR 1 — data-farm store + first consumer

stores/data-farm/teams.ts, id data-farm-teams.

• State: byId, order (the user's team list), currentTeamId, membershipByTeamId, loadState.

• Getters: list, current, get(id), isLoading, isLoaded.

• Actions: ensureLoaded() (→ getTeams), fetchOne(id) (→ getTeam), setCurrent(id), refreshCurrent() (replaces context.refreshTeam), upsert, remove, applyRealtime, clear.

• Consolidate the team-list responsibility currently split between context.js and account.js into this store. context.js may keep the derived "current route context" role but should read team data from here rather than owning a second copy.

• First consumer: migrate the team switcher (primary team-list view) to read list/current via ensureLoaded(), with its skeleton. This is what makes the PR demonstrable.

• Store created and normalized, with vitest unit tests.

• getTeams/getTeam/membership fetches moved behind store actions.

• Team switcher reads the store + skeleton; no direct teamApi there.

• clear() wired to team switch + logout.