Implement Buffer Parsers and Generic Map Class

This problem consists of two independent implementation tasks in C++:

1. Sequential Buffer Reader

Implement three functions to read data from a raw byte buffer starting at a given offset:

• readChar(): Reads the next byte as a char.
• readInt(): Reads the next 4 bytes as an int.
• readString(): Reads a 4-byte length followed by that many bytes as a std::string.

After each successful read, the offset must be advanced to the next unread byte. The functions should:

• Verify that sufficient bytes are available in the buffer before attempting a read.
• Safely convert the raw bytes to the requested type.
• Advance the offset only upon successful reading.
• Minimize unnecessary copying and memory allocations.

2. Generic Map Wrapper

Implement a template class that acts as a wrapper for either std::map<K, V> or std::unordered_map<K, V>. The key (K) and value (V) types are restricted to int or std::string.

The wrapper class should:

• Accept an instance of std::map or std::unordered_map in its constructor.
• Support inserting key-value pairs.
• Support querying a key and returning the associated value or a distinct "not found" indicator.
• Output all stored entries in key:value format, one entry per line. The order of output for std::unordered_map is not specified.
• Handle empty containers gracefully.

Template overloading or specialization may be used as needed.