Add new bugs to list

Author: AJenbo

docs/todo/bugs.md

@@ -15,4 +15,63 @@ within the same impact tier.
 
 ---
 
-No outstanding items.
+#### B12. Interface-extends-interface constants (and other members) not merged
+
+| | |
+|---|---|
+| **Impact** | Low-Medium |
+| **Effort** | Low-Medium |
+
+When an interface extends multiple parent interfaces (e.g.
+`interface CarbonInterface extends DateTimeInterface, JsonSerializable, UnitValue`),
+`resolve_class_with_inheritance` only walks the `parent_class` field (the
+first extended interface). The remaining parent interfaces stored in the
+`interfaces` list are not traversed for member merging.
+
+Then `resolve_class_fully_inner` calls `resolve_class_with_inheritance` on
+each interface collected from the class, but that inner call has the same
+limitation — it does not recurse into the interface's own `interfaces` list.
+
+**Reproducer:** `Illuminate\Support\Carbon::JANUARY` — the `JANUARY` constant
+lives on `Carbon\Constants\UnitValue`, which `CarbonInterface` extends (6th
+in the extends list). PHPantom reports "Member 'JANUARY' not found on class
+'Illuminate\Support\Carbon'".
+
+**Fix:** In `resolve_class_with_inheritance`, when processing an interface
+(or always), also merge members from all entries in `self.interfaces`, not
+just `parent_class`. Alternatively, make `resolve_class_fully_inner`
+recursively collect parent interfaces when resolving each interface.
+
+Affects 4 diagnostics in shared (Carbon month constants) and likely more in
+other projects that use interfaces with multi-extends chains.
+
+---
+
+#### B13. Variable type resolved from reassignment target inside RHS expression
+
+| | |
+|---|---|
+| **Impact** | Low |
+| **Effort** | Medium |
+
+When a variable is reassigned with an expression that references itself in
+the RHS arguments, PHPantom resolves the variable to the NEW type inside
+those arguments instead of the original type.
+
+**Reproducer:**
+```php
+public function requestToken(PaymentTokenRequest $request, ...): ... {
+    // $request is PaymentTokenRequest here
+    $request = new CreateRecurringSessionRequest(
+        paymentMethodReference: $request->uuid,  // ← PHPantom resolves $request as CreateRecurringSessionRequest
+    );
+}
+```
+
+PHP evaluates all arguments before performing the assignment, so `$request->uuid`
+should resolve against `PaymentTokenRequest`. PHPantom's variable definition
+offset tracking considers the new definition active too early — it should
+only take effect after the full RHS expression is evaluated.
+
+Affects 1 diagnostic in shared. Edge case but could appear in code that
+reuses variable names across reassignments with self-referencing expressions.