unify(worldbuilder): Merge Generals and Zero Hour WorldBuilder

[OmarAglan]

What changed

• Synchronized the Generals and Zero Hour WorldBuilder source and resource trees.
• Added the richer Zero Hour editor features to Generals, including ruler support, team object properties, layers, ambient-sound editing, and the expanded editor resources.
• Preserved game-specific behavior through RTS_GENERALS and RTS_ZEROHOUR guards.
• Preserved the Generals blend-tile serialization version and camera-direction controls.

Why

WorldBuilder had diverged between Generals and Zero Hour. The implementations must be behaviorally aligned before one shared copy can be moved to Core.

Impact

Both games retain their own WorldBuilder targets in this PR, but their 198 source/header files and shared resources are now identical.

Validation

• Generals and Zero Hour source/header trees compare identically
• All 198 source/header files are present in both CMake manifests
• Shared resource hashes match, excluding the intentional game-specific splash bitmap
• git diff --check
• Exactly one commit relative to the prerequisite branch

Stack

2 of 3. Depends on TheSuperHackers#3024 (unify/worldbuilder-prerequisites).

[OmarAglan]

Superseded by TheSuperHackers#3025.