Add: hiddenActivityBanners

[borislav-itskov]

Add: hiddenActivityBanners to activity.ts to allow for manually hiding the activity banner

This is the main change:

// do not show a banner for forcefully hidden banners
this.broadcastedButNotConfirmed
.filter(
  (op) =>
    !this.#hiddenActivityBanners.includes(
      `${op.accountAddr}-${op.networkId}-${op.timestamp}`
    )
)
...