wip(E2): partial nominal-identity/shadow work [stdlib E2 attempt-1 WIP checkpoint]

Incomplete WIP from a worker killed at the 30-min wall; committed as a
checkpoint so the resumed session continues on a clean tree. May not build.

src/ir/types.zig

@@ -332,11 +332,15 @@ pub const TypeTable = struct {
     tags: TagRegistry,
     /// Maps TypeInfo → TypeId for dedup of structural types
     intern_map: std.HashMap(TypeKey, TypeId, TypeKeyContext, 80),
-    /// Stable nominal identity: type-decl AST node → its TypeId. The
-    /// `fn_decl_fids` analogue — one entry per declaring node, so two
-    /// same-display-name declarations resolve to distinct TypeIds via their
-    /// own node pointer. Populated by the resolver when it assigns nominal ids.
-    type_decl_tids: std.AutoHashMap(*const ast.Node, TypeId),
+    /// Stable nominal identity: the declaring decl's pointer → its TypeId. The
+    /// `fn_decl_fids` analogue — one entry per declaring decl, so two
+    /// same-display-name declarations resolve to distinct TypeIds via their own
+    /// decl pointer. Keyed by the opaque `RawDeclRef` inner pointer (e.g.
+    /// `*const ast.StructDecl`) — the SAME pointer the import raw-facts hold and
+    /// `registerStructDecl` receives, so registration and resolution agree on
+    /// identity without threading the wrapping `ast.Node`. Populated by the
+    /// resolver (E2) as it assigns nominal ids.
+    type_decl_tids: std.AutoHashMap(*const anyopaque, TypeId),
     alloc: Allocator,
     /// Owns the element/param slices duped by the type constructors
     /// (`functionType*`, `closureType*`, `packType`). Freed wholesale in
@@ -353,7 +357,7 @@ pub const TypeTable = struct {
             .strings = StringPool.init(alloc),
             .tags = TagRegistry.init(alloc),
             .intern_map = std.HashMap(TypeKey, TypeId, TypeKeyContext, 80).init(alloc),
-            .type_decl_tids = std.AutoHashMap(*const ast.Node, TypeId).init(alloc),
+            .type_decl_tids = std.AutoHashMap(*const anyopaque, TypeId).init(alloc),
             .alloc = alloc,
             .slice_arena = std.heap.ArenaAllocator.init(alloc),
         };