fix(linear): avoid whole-batch failure when unrelated team cache breaks

[cursor]

Summary

• fix linear.Tracker.BatchPush to load workflow state caches lazily per team instead of preloading every configured team
• prevent an outage in an unrelated/misconfigured secondary Linear team from aborting pushes for healthy teams
• keep create paths using primary-team cache while update paths resolve and cache only the team they actually route to

Bug impact

In multi-team setups, the previous eager cache bootstrap failed the entire batch when any configured team returned an error from TeamStates, even when no issue in the current push targeted that team. This caused complete push failures for healthy teams.

Validation

• CGO_ENABLED=1 go test -tags gms_pure_go ./internal/linear -run 'TestBatchPush_DoesNotFailOnUnusedBrokenTeam|TestBatchPush_PerTeamStateCache'
• CGO_ENABLED=1 go test -tags gms_pure_go ./internal/linear
• make test (fails in this environment due existing unrelated setup issues: cmd/bd and internal/storage/dolt tests require external dependencies such as dolt binary / host behavior)