Refactor: Restructure project package hierarchy and add initial implementation for assembler instructions, shell commands, and exception handling.

src/jvmMain/kotlin/mtmc/asm/instructions/ErrorInstruction.kt

@@ -0,0 +1,23 @@
+package mtmc.asm.instructions
+
+import mtmc.asm.Assembler
+import mtmc.tokenizer.MTMCToken
+
+class ErrorInstruction(
+  labels: List<MTMCToken>,
+  instruction: MTMCToken,
+  error: String
+) : Instruction(
+  InstructionType.ERROR,
+  labels,
+  instruction
+) {
+
+  init {
+    addError(instruction, error)
+  }
+
+  override fun genCode(output: ByteArray, assembler: Assembler) {
+    // do nothing
+  }
+}