I have located the first commit in the bitcoin/bitcoin repo on GitHub [1]. However, there is no single occurrence of "Poker".

In the original-bitcoin repo I've found CPokerLobbyDialogBase class [2]. So I can partially confirm your theory.

According to bitcoin.com in the early stages of the project there was an idea for implementing on-chain poker game [3].

> Bitcoin was simply designed to be an in game currency for a poker game

Could you back this theory with some evidence?

[1]: https://github.com/bitcoin/bitcoin/commit/4405b78d6059e536c3...

[2]: https://github.com/trottier/original-bitcoin/blob/92ee8d9a99...

[3]: https://news.bitcoin.com/satoshis-pre-release-bitcoin-code-c...