Add production observability: Sentry, pino, and sharp badge encoding.

Sentry is opt-in via DSN env vars; logger uses structured pino JSON in prod; badge uploads are normalized to GIF with sharp.

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

src/env.ts

@@ -73,6 +73,13 @@ const schema = z.object({
 	REDIS_URL: z.string().optional(),
 	// Logging level.
 	LOG_LEVEL: z.enum(["debug", "info", "warn", "error"]).optional(),
+	// Optional Sentry — no-op when unset.
+	SENTRY_DSN: z.string().url().optional(),
+	NEXT_PUBLIC_SENTRY_DSN: z.string().url().optional(),
+	SENTRY_ORG: z.string().optional(),
+	SENTRY_PROJECT: z.string().optional(),
+	SENTRY_AUTH_TOKEN: z.string().optional(),
+	APP_VERSION: z.string().optional(),
 });
 
 type Env = z.infer<typeof schema>;