fix(briefing): exclude paused-project tasks from briefing tooling

list_notes gains exclude_paused_projects; list_tasks tool sets it when
no explicit project filter is given. Paused projects no longer leak
tasks into briefings or list_tasks results.

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

src/fabledassistant/services/tools.py

@@ -1509,6 +1509,7 @@ async def execute_tool(
                 due_after=_parse_due_date(arguments.get("due_after")),
                 project_id=project_id,
                 milestone_id=milestone_id,
+                exclude_paused_projects=project_id is None,
                 limit=int(arguments.get("limit", 10)),
                 sort="due_date",
                 order="asc",