fix(lint): use model_validate for Filter default construction

Pyright doesn't recognize Pydantic Field() defaults in constructors.
Use model_validate({}) which pyright understands.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ImTotem

src/bcsd_api/member/resolvers.py

@@ -50,7 +50,7 @@ def resolve_members(
 ) -> PagedMembers:
     ctx = info.context
     require_user(ctx)
-    filt = _to_filter(filter) if filter else MemberFilter()
+    filt = _to_filter(filter) if filter else MemberFilter.model_validate({})
     paged = service.list_members(ctx.member_repo, filt)
     items = [_to_member(m) for m in paged.items]
     return PagedMembers(

src/bcsd_api/shorten/resolvers.py

@@ -67,7 +67,7 @@ def resolve_links(
 ) -> PagedLinks:
     ctx = info.context
     require_user(ctx)
-    filt = _to_filter(filter) if filter else LinkFilter()
+    filt = _to_filter(filter) if filter else LinkFilter.model_validate({})
     paged = service.list_links(ctx.link_repo, filt)
     items = [_to_link(r) for r in paged.items]
     return PagedLinks(