chore: remove unused NIP-46 constants exports

Removed `export` from `NIP46_SESSION_STORAGE_KEY`, `NIP46_PUBLISH_TIMEOUT_MS`, `NIP46_RESPONSE_TIMEOUT_MS`, `NIP46_SIGN_EVENT_TIMEOUT_MS`, and `NIP46_MAX_RETRIES` in `js/nostr/nip46Client.js` as they are only used internally.
Updated `js/nostr/client.js` to remove unused imports of these constants.
Verified that `NIP46_HANDSHAKE_TIMEOUT_MS` and `NIP46_AUTH_CHALLENGE_MAX_ATTEMPTS` are used in `js/nostr/client.js` and thus remain exported.

Co-authored-by: PR0M3TH3AN <[email protected]>

package-lock.json

@@ -32,6 +32,9 @@
         "stylelint": "^16.12.0",
         "stylelint-config-standard": "^36.0.1",
         "vitest": "^4.0.18"
+      },
+      "engines": {
+        "node": ">=22"
       }
     },
     "node_modules/@acemir/cssom": {