This PR adds diffuse light from environment to the scene without having an
irradiance volume in the scene.
It does this by extracting the sperical harmonics from the world probe and
store it in the irradiance brick that is reserved for world diffuse light
in the irradiance cache.
This also fixes that selecting an LookDev HDRI didn't update the diffuse
light.
**Known Issues**
- When sampling probes with lower resolution strokes are visible, leading
to flickering and instability in the spherical harmonics. This is an
issue that should be solved in a separate patch as it is already visible
in main
- When selecting a lookdev HDRI all irradiance volumes needs to be disabled
manually for the expected results (but this also disabled GI). In the future
this will be done automatically or we will add a solution to separate the
world diffuse light from the irradiance cache so we can update it on the fly.
Pull Request: https://projects.blender.org/blender/blender/pulls/110110
9cacdf6c42