feat: support source pointers and references

source/diagnostics/diagnostics.hon

@@ -89,6 +89,11 @@ Code :: enum {
     unreachable_match_arm
     invalid_match_capture
     inactive_union_field
+    invalid_pointer_type
+    invalid_address_operand
+    invalid_dereference
+    invalid_pointer_assignment
+    invalid_pointer_access
 }
 
 Diagnostic :: struct {
@@ -199,5 +204,10 @@ messages :: $enummap.init(Code, []u8, {
     unreachable_match_arm = "match arm is unreachable",
     invalid_match_capture = "payload capture requires compatible nonvoid tagged union variants",
     inactive_union_field = "tagged union field is not active",
+    invalid_pointer_type = "pointer requires a supported concrete pointee type",
+    invalid_address_operand = "address-of requires addressable storage",
+    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",
 })