[Enhancement] Uninitialized submodules need visual indication in list

[goran-w]

Currently, when having a mix of initialized and non-initialized submodules under SUBMODULES in the left sidebar, these are not distinguished visually in any way (except by the badge in tooltip, on individual hover).

This becomes confusing, for example when double-clicking a "stealthily" non-initialized submodule and nothing happens.

Any indication that's permanently visible in the SUBMODULES list would be sufficient, like changing the color of the submodule-icon (to the same color as the orange 'not initialized' badge in the tooltip) or replacing the icon (with a crossed-out submodule-icon, similar to the hide-eye-icon, perhaps).