Update CodeQL workflow to resolve setup issue

• Fixed the issue with 'setup-codeql' action by verifying and updating to the correct version.
• Ensured correct configuration for CodeQL analysis and database initialization.
• Workflow now correctly sets up the CodeQL environment, initializes the database, and performs security analysis.

1. In src/main.rs:

• Added a simple program to demonstrate the VM's functionality.
• Created instances of IOController and MemoryManagementUnit.
• Loaded the program into the CPU's memory and started execution.

2. In src/cpu.rs:

• Implemented the load_program method to load a program into memory.
• Created the main run method that executes the fetch-decode-execute cycle until the CPU is halted.
• Modified the decode_and_execute method to fetch operands for each instruction.
• Added a halted flag and a HALT instruction to stop execution.
• Implemented a print_registers method for debugging.
• Updated all instruction methods to take two operands.
• Added a comprehensive test that runs a small program in the VM.

1. Expanded the instruction set with new logical operations: and, or, xor, and not.
2. Added shift operations: shl (shift left) and shr (shift right).
3. Implemented a comparison operation cmp that sets flags based on the result.
4. Added jump instructions: jmp (unconditional jump), je (jump if equal), jne (jump if not equal), jg (jump if greater), and jl (jump if less).
5. Introduced a flags register to store comparison results.
6. Modified the decode function to accommodate the expanded instruction set.
7. Added new unit tests to verify the correctness of the new instructions.

1. A new io.rs file that implements the IOController and IODevice trait.
2. The ConsoleDevice struct implements basic console I/O operations.
3. The CPU struct now includes an IOController.
4. Two new instructions, input and output, have been added to interact with I/O devices.
5. The main.rs file has been updated to create an IOController and pass it to the CPU.
6. A MockIOController has been added for testing purposes.
7. Additional tests have been added to verify the correctness of I/O operations.

1. A new memory.rs file that implements the MemoryManagementUnit struct.
2. The MemoryManagementUnit provides methods for reading and writing both bytes and words (32-bit values) to memory.
3. The CPU struct now uses the MemoryManagementUnit instead of a raw memory array.
4. Two new instructions, load and store, have been added to interact with memory.
5. The fetch method now uses the MMU to read instructions from memory.
6. Additional tests have been added to verify the correctness of memory operations and the new instructions.

1. We've defined a CPU struct that holds the essential components: registers, program counter, memory, and an instruction set.
2. The new() function initializes the CPU with default values and sets up the instruction set.
3. We've implemented a basic fetch-decode-execute cycle in the run() method.
4. The instruction set includes four basic arithmetic operations: add, subtract, multiply, and divide.
5. Each instruction operates on two registers, with the result stored in the first register.
6. We've included a simple opcode format that allows for future expansion.
7. Error handling is implemented for unknown opcodes and division by zero.
8. Unit tests are included to verify the correctness of each arithmetic operation.