feat: complete memory representation gate

source/diagnostics/diagnostics.hon

@@ -94,6 +94,11 @@ Code :: enum {
     invalid_dereference
     invalid_pointer_assignment
     invalid_pointer_access
+    null_unwrap
+    invalid_slice_bounds
+    sentinel_mismatch
+    overlapping_memory_copy
+    unsupported_foreign_call
 }
 
 Diagnostic :: struct {
@@ -209,5 +214,10 @@ messages :: $enummap.init(Code, []u8, {
     invalid_dereference = "dereference requires a pointer",
     invalid_pointer_assignment = "pointer assignment requires a mutable pointee",
     invalid_pointer_access = "pointer does not refer to live accessible storage",
+    null_unwrap = "cannot unwrap a null optional",
+    invalid_slice_bounds = "slice bounds are invalid",
+    sentinel_mismatch = "slice sentinel does not match the expected value",
+    overlapping_memory_copy = "memory copy source and destination overlap",
+    unsupported_foreign_call = "foreign function calls are unsupported by the interpreter",
 })