Resolve "Update regex used for profile name validation" & some fixes

Closes: #119 (closed)

Work done:

• Changed rules for profile name validation (less restricted, allow for @ in name - just like beekeeper does)
• Fix flicker on witness details (and possible flicker in pending transfers)
• Update SavingsProvider to latest changes in providers
• Fix issue with race between data provider and data watcher
• Fix possible bug in transfer from savings request_id calculation

Requires: - !283 (merged) - hive!1178 (merged)

Blocked until beekeeper supports "@" in wallet name. Currently it does not. ~~Check the status of: ~~~~https://gitlab.syncad.com/hive/hive/-/blob/master/programs/beekeeper/core/wallet_manager_impl.cpp?ref_type=heads#L24~~ ~~message: Only alphanumeric and '._-' chars are allowed~~