Allow extension settings to be configured at the team level

Extension settings can only be configured at the user level. Developers working across multiple teams must manually switch settings when moving between team contexts. For example, with the Claude extension, a developer on both Development and Modernization teams can only specify one GitHub repository and must manually update it when switching teams.

Lost productivity from manual configuration switching. Risk of errors like sending features to the wrong repository. Discourages extension adoption.

Allow extension settings to be configured per team, not just per user. When working in a team's context, automatically use that team's extension configuration.