Eda RPG - v0.8

feat(content): add illustrations and restructure gm guide

Integrate 16 new images across the rulebooks and bestiary to enhance
visual presentation. Restructure the "World of Eda" Tome into a formal
chapter-based outline and update the project's CSS to handle responsive
image placement, including side-floated illustrations for creature stat
blocks. Additionally, establish a centralized art placement plan for
tracking assets and update .gitignore for build artifacts.