Refactor item validation in ReactorInputInventory to use CNTags for better maintainability

[Giovanniricotta2002]

This pull request refactors the codebase to replace hardcoded item checks with tag-based checks, improving flexibility and maintainability. Additionally, wildcard imports were introduced in one file. The most important changes are summarized below:

Refactoring to use tag-based item checks:

• Updated calculateHeat in ReactorControllerBlockEntity to replace hardcoded item ID checks ("createnuclear:uranium_rod" and "createnuclear:graphite_rod") with checks using CNTags.CNItemTags.FUEL.tag and CNTags.CNItemTags.COOLER.tag. This change applies to both the main loop and proximity heat calculations. [1] [2]
• Modified isItemValid in ReactorInputInventory to use CNTags.CNItemTags.FUEL.matches and CNTags.CNItemTags.COOLER.matches instead of directly comparing items to CNItems.URANIUM_ROD and CNItems.GRAPHITE_ROD.

Import changes:

• Replaced specific imports with a wildcard import (import net.nuclearteam.createnuclear.*) in ReactorControllerBlockEntity. This reduces verbosity but may introduce unnecessary imports.
• Added the CNTags import in ReactorInputInventory to support the tag-based checks.