Working on VM-based obfuscation #1329

Have a really great progress.

VM obfuscation is almost complete, including:
• Functions: Regular, arrow, IIFE, async/await, generators (function*, yield, yield*)
• Parameters: Regular, rest (...args), default (a = 10)
• Variables: var, let, const with proper scoping and TDZ
• Operators: Arithmetic, logical, comparison, bitwise, nullish coalescing (??)
• Control Flow: if-else, switch, for, while, do-while, for-of, for-in, break, continue
• Labeled Statements: label: statement with break label / continue label
• Iterators: Full iterator protocol support (Symbol.iterator, custom iterators)
• Objects: Literals, property access, methods, shorthand, getters/setters, spread
• Arrays: Literals, methods, destructuring, spread
• Classes: Declarations, expressions, inheritance, super, static members
• Error Handling: try-catch-finally
• Types: typeof, instanceof, Symbol, BigInt, RegExp, WeakMap, WeakSet
• Optional Chaining: ?. and ?.[] operators

Covered a lot (but still probably not all) of tdz/shadowing edge cases.

VM obfuscation can obfuscate the obfuscator itself (now in ES6+ mode, minified code, so it contains a large number of different TDZ/shadowing cases), and after being VM obfuscated, it works properly.