feat: support compound updates and bitwise operators

source/diagnostics/diagnostics.hon

@@ -126,6 +126,7 @@ Code :: enum {
     missing_metadata_import
     invalid_metadata_abi
     invalid_undefined
+    invalid_shift_count
 }
 
 Diagnostic :: struct {
@@ -179,6 +180,7 @@ messages :: $enummap.init(Code, []u8, {
     type_mismatch = "incompatible value type",
     invalid_operand = "operator requires compatible operand types",
     integer_division = "division requires float operands",
+    invalid_shift_count = "shift count must be smaller than the integer bit width",
     not_callable = "value is not callable",
     argument_count_mismatch = "argument count does not match the function signature",
     cannot_infer_type = "cannot infer a type without a type anchor",