Audit and consolidate Roster name/tag field aliases

### Description

The `Roster` class currently maintains separate properties for similar naming concepts that could potentially be consolidated:

Name vs RosterName vs TeamName
Tag vs RosterTag vs TeamTag

These field aliases exist to handle different API response shapes (team-context vs player-context), but once usage patterns are fully audited, we should consider collapsing these into unified properties.
Location

File: `src/lib/common/Roster.ts` (line ~8)
### Tasks

- [ ] Audit all current usages of the name/tag properties across the codebase
- [ ] Document which API endpoints return which field variations
- [ ] Determine if consolidation is feasible without breaking changes
- [ ] If feasible, refactor to use single properties with appropriate fallback logic

### Notes

This refactoring would simplify the API surface and reduce confusion about which property to use in different contexts.