fix(reports): fix churn query crash and improve error reporting (#51)

The /api/reports/clients endpoint was crashing with a 500 on every request
because a raw JavaScript Date passed into a sql template literal in .having()
cannot be serialized by postgres-js. The fix serializes it as an ISO string
with an explicit ::timestamptz cast.

Also adds reportsRouter.onError() and improves the frontend error message
to surface which specific endpoint failed and why.

Fixes #49
Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/api/src/routes/reports.ts

@@ -16,6 +16,11 @@ import {
 
 export const reportsRouter = new Hono();
 
+reportsRouter.onError((err, c) => {
+  console.error("[reports] unhandled error:", err);
+  return c.json({ error: "Internal server error", message: err.message }, 500);
+});
+
 // ─── Helpers ──────────────────────────────────────────────────────────────────
 
 function parseDate(value: string | undefined, fallback: Date): Date {

apps/web/src/pages/Reports.tsx

@@ -176,8 +176,23 @@ export function ReportsPage() {
         fetch(`/api/reports/clients?${qs}`),
       ]);
 
-      if (!summRes.ok || !revRes.ok || !apptRes.ok || !svcRes.ok || !clientRes.ok) {
-        throw new Error("Failed to load report data");
+      const failures = [
+        ["summary", summRes],
+        ["revenue", revRes],
+        ["appointments", apptRes],
+        ["services", svcRes],
+        ["clients", clientRes],
+      ].filter(([, r]) => !(r as Response).ok);
+      if (failures.length > 0) {
+        const details = await Promise.all(
+          failures.map(async ([name, r]) => {
+            const res = r as Response;
+            let body = "";
+            try { body = await res.text(); } catch { /* ignore */ }
+            return `${name} (HTTP ${res.status}${body ? `: ${body.slice(0, 120)}` : ""})`;
+          })
+        );
+        throw new Error(`Failed to load report data — ${details.join(", ")}`);
       }
 
       const [summData, revData, apptData, svcData, clientData] = await Promise.all([