Add inning counter

[krazkidd]

The inning should be tracked along with the scores.

See this mocked up example:

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Requirements:

1. Sensible placement on the scoreboard page in a way that doesn't distract from the team scores (between or above the team scorecards--if between, the emoji react will need to be moved).
2. Responsivity.
3. Hide increment/decrement buttons in shared view.
4. The inning counter must not go below 1. (Use the same solution as #15, if available.)
5. The inning number must be persisted in the Firestore backend.

[krazkidd]

This was implemented on main. There is no PR.