Use tRPC in other group pages (#249)

* Use tRPC in group edition + group layout

* Use tRPC in group modals

* Use tRPC in group stats

* Use tRPC in group activity

src/trpc/routers/groups/get.procedure.ts

@@ -0,0 +1,19 @@
+import { getGroup, getGroupExpensesParticipants } from '@/lib/api'
+import { baseProcedure } from '@/trpc/init'
+import { TRPCError } from '@trpc/server'
+import { z } from 'zod'
+
+export const getGroupProcedure = baseProcedure
+  .input(z.object({ groupId: z.string().min(1) }))
+  .query(async ({ input: { groupId } }) => {
+    const group = await getGroup(groupId)
+    if (!group) {
+      throw new TRPCError({
+        code: 'NOT_FOUND',
+        message: 'Group not found.',
+      })
+    }
+
+    const participantsWithExpenses = await getGroupExpensesParticipants(groupId)
+    return { group, participantsWithExpenses }
+  })