feat(ops): health-fail alerts, optional DB backup, admin UX polish

Wire jobs-worker health probes to Discord/email alerts with cooldown, optional mysqldump, rate-limit /api/health, mark-all-read alerts, ConfirmDialog on destructive admin actions, and raise coverage floors.

Co-authored-by: Cursor <[email protected]>

src/lib/staff-smoke-contract.test.ts

@@ -179,6 +179,23 @@ describe("staff smoke contract", () => {
 		);
 	});
 
+	it("ships ops health alerts, optional DB backup, and health rate limit", () => {
+		const worker = readFileSync("scripts/jobs-worker.ts", "utf8");
+		expect(worker).toContain("checkOpsHealth");
+		expect(worker).toContain("healthDegraded");
+		expect(worker).toContain("backupDatabase");
+		expect(readFileSync("src/lib/services/alert.ts", "utf8")).toContain(
+			"healthDegraded",
+		);
+		expect(readFileSync("src/app/api/health/route.ts", "utf8")).toContain(
+			"rateLimit",
+		);
+		expect(readFileSync("src/actions/admin-alerts.ts", "utf8")).toContain(
+			"markAllAlertsRead",
+		);
+		expect(readFileSync("src/env.ts", "utf8")).toContain("DB_BACKUP_DIR");
+	});
+
 	it("documents local-only photo file purge", () => {
 		expect(readFileSync("src/app/admin/photos/page.tsx", "utf8")).toContain(
 			"purgeHint",