Refactor login with store.SavePeer (#2334)

This pull request refactors the login functionality by integrating store.SavePeer. The changes aim to improve the handling of peer login processes, particularly focusing on synchronization and error handling.

Changes:
- Refactored login logic to use store.SavePeer.
- Added checks for login without lock for login necessary checks from the client and utilized write lock for full login flow.
- Updated error handling with status.NewPeerLoginExpiredError().
- Moved geoIP check logic to a more appropriate place.
- Removed redundant calls and improved documentation.
- Moved the code to smaller methods to improve readability.

management/server/status/error.go

@@ -95,3 +95,8 @@ func NewUserNotFoundError(userKey string) error {
 func NewPeerNotRegisteredError() error {
 	return Errorf(Unauthenticated, "peer is not registered")
 }
+
+// NewPeerLoginExpiredError creates a new Error with PermissionDenied type for an expired peer
+func NewPeerLoginExpiredError() error {
+	return Errorf(PermissionDenied, "peer login has expired, please log in once more")
+}