Add code codex

**Font Project Git Repo URL:**
https://github.com/orld634/code-codex-font.git

**Super short description of the Font Family:**
Code Codex is a retro pixel-art style font family designed for video games, pixel-perfect user interfaces, and retro digital artwork. It features custom serif structures on vertical letters like the "I" to ensure balanced visual weight and spacing.

**Requirements:**
By opening this issue, I confirm the project meets the following requirements:

- [x] The entire font project is available in a Github repository (repo) and licensed under the [OFL](https://openfontlicense.org)
- [x] The font files (.ttf) are in the `fonts/ttf/` directory.
- [x] An `OFL.txt` file is included in the repository.
- [x] A comprehensive `README.md` file is included in the repository.

Start by reviewing the Code Codex repository at https://github.com/orld634/code-codex-font.git, especially fonts/ttf/, OFL.txt, and README.md. Verify that the font files, licensing, and project documentation meet the stated requirements; done means the font is accepted into Google Fonts according to the repository's contribution process.

Written by the indexing model from the issue text.