fix: byte formatting + exactOptionalPropertyTypes

fmtBytes used 1<<40 — a 32-bit shift in JS evaluates to 1<<8=256, so every
value >=256 bytes rendered as TB. Also drop undefined-valued props that
exactOptionalPropertyTypes rejects in incident/status-page bodies.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/frontend/src/pages/StatusPagesPage.tsx

@@ -57,7 +57,7 @@ export function StatusPagesPage() {
 		const { error } = await api.POST("/api/status-pages", {
 			body: {
 				title: pTitle.trim(),
-				slug: pSlug.trim() || undefined,
+				...(pSlug.trim() ? { slug: pSlug.trim() } : {}),
 				description: pDesc.trim(),
 				monitorIds: pMonitors,
 			},