Adds Lua (.lua) and Luau (.luau) extraction — functions, methods with receivers, type aliases (Luau), require imports (incl. Roblox instance-path), and call edges. Vendors the ABI-15 Lua and ABI-14 Luau tree-sitter grammars. Addresses #232.
Renames the `.claude/skills/audit/` directory and all internal references to `agent-eval`, aligning the skill name with the `/agent-eval` command it invokes.