fix: typeof returns 'boolean' for boolean variables instead of 'number'

[cs01]

Summary

• typeof boolVar now correctly returns "boolean" instead of "number"
• Boolean variables were tracked as SymbolKind.Number in the variable allocator — changed to SymbolKind.Boolean in all allocation paths (null-initialized, declared-type, and literal-initialized)
• Added isBoolean() check in generateTypeof() so typeof dispatches correctly for boolean variables
• Fixed duplicate isComparisonOp function name collision between templates.ts and concatenation.ts that broke self-hosting

Test plan

• New test fixture types/typeof-boolean.ts covers literal booleans, boolean variables, and comparison results
• All existing tests pass
• Self-hosting Stage 1 passes