Properly handle texture size limit

[Nicolas-Ferre]

Problem
WGPU defines a texture dimension limit. If this size is exceeded, the app panics.

Feature
Propertly handle textures with size higher than limit.

Tasks

• Set up correctly the WGPU limits
• Handle depth texture in case of big resolution (e.g. 4K)
• Handle too big user textures
• Handle too big text textures (reduce font height)