fix: skip optional deps to avoid sharp compilation on Cloudflare Pages

Added omit=optional to .npmrc to prevent @xenova/transformers from
trying to compile sharp with native dependencies. Sharp is only used
for server-side image processing which isn't needed in the browser.

Also added override for sharp version in package.json as fallback.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.npmrc

@@ -1,3 +1,5 @@
 legacy-peer-deps=true
 strict-peer-dependencies=false
 auto-install-peers=true
+# Skip optional dependencies to avoid native compilation issues (e.g., sharp in @xenova/transformers)
+omit=optional

package.json

@@ -92,5 +92,8 @@
 	},
 	"engines": {
 		"node": ">=20.0.0"
+	},
+	"overrides": {
+		"sharp": "0.33.5"
 	}
 }