Merge pm (panel-based access, supervisor role) onto the restored RBAC base

Reverting 253c922 first made this merge small — only two conflicts:
- MobileTabBar: supervisor null-check combined with v7's /review hiding
- ArrivalsPage: pm's PM+supervisor scoping combined with v8's 3-way fetch
  (transfers) and its transfer-receive helpers, plus pm's canAccess gate

backend/app/schemas/procurement.py

@@ -352,3 +352,16 @@ class ReceiptUpdate(APIModel):
     received_qty: Decimal | None = Field(default=None, gt=0)
     on_time: bool | None = None
     quality_note: str | None = None
+
+
+class UserPanelsUpdate(APIModel):
+    """Replace the user's panel assignments. هر پنل: 'full' | 'limited' —
+    پنل غایب یعنی تخصیص نداشتن و کلید آن حذف می‌شود."""
+
+    panels: dict[str, str] = Field(default_factory=dict)
+
+
+class UserPanelProjectsUpdate(APIModel):
+    """Replace the user's project memberships (M:N — جدا از مسئولیت پروژه)."""
+
+    project_ids: list[UUID] = Field(default_factory=list)