[ltk_overlay][Phase 1] Create ltk_overlay crate structure

[Crauzer]

Create the new ltk_overlay workspace crate with initial structure.

Tasks

• Create crate directory structure
• Setup Cargo.toml with dependencies
• Create basic module structure (lib.rs, builder.rs, error.rs, game_index.rs, utils.rs)
• Define public API types (OverlayBuilder, EnabledMod, etc.)
• Add basic documentation (README.md)
• Add to workspace members in root Cargo.toml

Acceptance Criteria

• Crate compiles successfully
• Basic types are defined
• Module structure is in place
• Unit tests compile (can be placeholder)

Status

✅ COMPLETED - Crate scaffold created and compiles successfully.

Related:

• Epic: [Epic] Implement WAD Overlay/Profile Builder (ltk_overlay) #85
• Phase: 1 (Core Extraction)

[Crauzer]

✅ Completed - ltk_overlay crate created and compiles successfully. See commit for crate scaffold.