Fix repeated Amber push config prompts and honor disabled push notifications

[nikitawvi]

Changes:

• Prevent setPushNotifications from configuring push when enablePushNotification is false
• Cache Amber signer denial for PUSH_CONFIG to avoid repeated signing requests for the same key/device
• Track last push deviceId to skip redundant push config sends
• Reset push‑denial cache on login/logout when signer changes

[nikitawvi]

@Darecjo @Seddik-Boukhalfa Hello!

fixed #31

[Seddik-Boukhalfa]

We will look into it.