fix: register errand router in appRouter and fix build errors

errandProcedures was defined but never imported/spread into the app
router, causing "No procedure found on path errand.create". Also fixed
nullable projectId TS errors in delete/abandon and added missing
sendUserMessage to test mocks.

apps/server/cli/index.ts

@@ -1878,7 +1878,7 @@ See the Codewalkers documentation for .cw-preview.yml format and options.`;
           : `.cw-worktrees/${id}`;
         console.log(`Resolve conflicts in worktree: ${worktreePath}`);
         console.log('Conflicting files:');
-        for (const f of errand.conflictFiles ?? []) {
+        for (const f of (errand as any).conflictFiles ?? []) {
           console.log(`  ${f}`);
         }
         console.log('After resolving: stage and commit changes in the worktree, then run:');