M1: OrgBoard — organizations, teams, seats, the board & cartable

OrgBoard module (references SharedKernel only; RBAC via ICurrentUser/IPermissionService):
- Organization, Team, Seat (human/open/ai), WorkItem (board task: type, status, assignee,
  parent) entities; internal OrgBoardDbContext (schema "orgboard") + InitialOrgBoard
  migration; design-time factory. (WorkItem avoids the System.Threading.Tasks.Task clash.)
- Endpoints under /api/orgboard, every mutation permission-checked at the scope chain
  [team, org]: POST /organizations, POST/GET /teams, POST /tasks, GET /board (columns
  backlog->in progress->in review->done), PATCH /tasks/{id}/move, /assign, GET /cartable.

Test isolation: integration tests now use IClassFixture so each class gets its own
pgvector container (the bootstrap-once rule made a shared container collide).

Verified: build green; ArchitectureTests 8/8 (OrgBoard references only SharedKernel);
IntegrationTests 12/12 incl. a new board flow — owner sets up org+team, creates/moves/
assigns a task, sees it on the board and in the cartable; an invited Member can view the
board but is 403'd from creating a team.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Modules/TeamUp.Modules.OrgBoard/TeamUp.Modules.OrgBoard.csproj

@@ -1,10 +1,17 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-  <!-- A self-contained module. References SharedKernel ONLY (ASP.NET flows transitively for the
-       IModule seam). M1 adds this module's EF/Npgsql/FluentValidation/Mapperly packages when it
-       gains an (internal) DbContext and validators. It must never reference another module. -->
+  <!-- Org, products, teams, seats, and the task/board model (M1). References SharedKernel only;
+       permission checks use ICurrentUser/IPermissionService from SharedKernel (implemented by
+       Identity), so OrgBoard never references another module. -->
   <ItemGroup>
     <ProjectReference Include="..\..\Shared\TeamUp.SharedKernel\TeamUp.SharedKernel.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" PrivateAssets="all" />
+    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <PackageReference Include="FluentValidation" />
+  </ItemGroup>
+
 </Project>