feat(psa): add PaginatedTicketResult type, update provider search_tickets signature

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/services/psa/base.py

@@ -13,6 +13,7 @@ from .types import (
     PSAConfiguration,
     PSATimeEntry,
     PSABoard,
+    PaginatedTicketResult,
 )
 
 
@@ -28,7 +29,7 @@ class PSAProvider(ABC):
         ...
 
     @abstractmethod
-    async def search_tickets(self, query: str, **filters) -> list[PSATicket]:
+    async def search_tickets(self, query: str, **filters) -> PaginatedTicketResult:
         ...
 
     @abstractmethod

backend/app/services/psa/types.py

@@ -73,6 +73,13 @@ class PSABoard(BaseModel):
     inactive: bool = False
 
 
+class PaginatedTicketResult(BaseModel):
+    items: list[PSATicket]
+    total: int
+    page: int
+    page_size: int
+
+
 class NoteType:
     INTERNAL_ANALYSIS = "internal_analysis"
     RESOLUTION = "resolution"