fix: small bug for PGXL fan and ultrabeam direction

internal/ultrabeam/ultrabeam.go

@@ -68,6 +68,13 @@ type Client struct {
 	running    bool
 	seqNum     byte
 	seqMu      sync.Mutex
+
+	// Optimistic pattern direction kept until the antenna's status poll reports
+	// it (or it ages out) — the motors take a second or two, and a stale poll in
+	// between would otherwise snap the UI back to the old direction.
+	pendingDir    int
+	pendingDirAt  time.Time
+	pendingDirSet bool
 }
 
 type Status struct {
@@ -199,6 +206,14 @@ func (c *Client) pollLoop() {
 			}
 
 			c.statusMu.Lock()
+			// Keep a just-commanded direction until the antenna reports it.
+			if c.pendingDirSet {
+				if time.Since(c.pendingDirAt) > 4*time.Second || status.Direction == c.pendingDir {
+					c.pendingDirSet = false
+				} else {
+					status.Direction = c.pendingDir
+				}
+			}
 			c.lastStatus = status
 			c.statusMu.Unlock()
 
@@ -449,6 +464,14 @@ func (c *Client) SetFrequency(freqKhz int, direction int) error {
 	}
 
 	_, err := c.sendCommand(CMD_FREQ, data)
+	if err == nil {
+		c.statusMu.Lock()
+		c.pendingDir, c.pendingDirAt, c.pendingDirSet = direction, time.Now(), true
+		if c.lastStatus != nil {
+			c.lastStatus.Direction = direction // reflect immediately
+		}
+		c.statusMu.Unlock()
+	}
 	return err
 }