feat: Ultrabeam over USB, Paper QSL from the awards grid, per-role schemas

Ultrabeam on a serial port never worked, and three faults were stacked so
each hid the next:

  - Stop() did not wait for the poll loop, so a stopped client kept the COM
    port. Every later client then failed with "Serial port busy" — the
    program holding it being OpsLog itself.
  - startUltrabeam tore the old client down CONCURRENTLY with starting the
    new one, and "Test connection" built a second client on a port already
    ours. Harmless over TCP, fatal on a port with one owner.
  - A silent serial port returns (0, nil) and bufio retries that a hundred
    times: a 4 s timeout became ~7 minutes of a frozen poll loop logging
    nothing.

The controller then answered at once. Confirmed on hardware: the USB cable
presents TWO COM ports, only the second reaches the controller, and only at
19200 baud — so the speed is pinned in code (an FTDI cable opens at any
speed, and a wrong one is indistinguishable from a dead controller) and the
port field says which one to pick. The first exchange after each connect is
hex-dumped, which separates silence from a wrong baud from a misread frame.

Databases now carry only the tables their role needs. Every target used to
get the whole migration set, so a shared MySQL logbook grew settings and
station_profiles tables nothing ever wrote to — an operator inspecting the
server could not tell which copy was authoritative. Statements are filtered
by role, unknown tables are kept in both (fail-safe), and existing databases
are cleaned once, dropping only EMPTY tables. Settings → Database gains a
Compact button, since SQLite frees pages inside the file and never shrinks it.

Also:
  - Awards: the callsigns behind a cell open the QSL Manager on Paper QSL,
    searched, ready for the card dates.
  - The record button no longer goes missing after an update: whether manual
    recording is possible is a per-profile question that was asked once, at
    startup, before the profile was known.
  - Alert rules and filter presets confirm that they were saved.
  - Spot clicks on the radio panadapter carry the POTA park into F3.
  - The build gate is re-checked wherever the active callsign can change; it
    ran at startup alone, and a fresh install has no callsign then.

internal/ultrabeam/stop_test.go

@@ -0,0 +1,80 @@
+package ultrabeam
+
+import (
+	"bufio"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+)
+
+// Stop must not return while the poll loop is still alive: on a serial link the
+// loop owns the port, and a client that outlives its Stop is what turned every
+// later connection into "Serial port busy".
+func TestStopWaitsForPollLoop(t *testing.T) {
+	// A transport that cannot connect, so the loop spends its life in open() and
+	// the reconnect path — the state the real fault happened in.
+	c := New(Transport{Mode: "tcp", Host: "127.0.0.1", Port: 1})
+	if err := c.Start(); err != nil {
+		t.Fatal(err)
+	}
+	done := c.done
+	time.Sleep(50 * time.Millisecond)
+	c.Stop()
+	select {
+	case <-done:
+	default:
+		t.Fatal("Stop returned while the poll loop was still running")
+	}
+	// Stopping twice must not panic on the closed channel.
+	c.Stop()
+}
+
+func TestPortBusyHint(t *testing.T) {
+	// The Windows driver's own words, and the ones an operator has to act on.
+	if h := portBusyHint("serial", "COM13", errors.New("Serial port busy")); !strings.Contains(h, "COM13") {
+		t.Fatalf("no hint for a busy port: %q", h)
+	}
+	if h := portBusyHint("serial", "COM13", errors.New("Access is denied.")); h == "" {
+		t.Fatal("no hint for access denied")
+	}
+	// A port that simply is not there is a different problem, and saying "another
+	// program has it" would send the operator hunting for a program that is not
+	// running.
+	if h := portBusyHint("serial", "COM13", errors.New("The system cannot find the file specified.")); h != "" {
+		t.Fatalf("hinted at a busy port for a missing one: %q", h)
+	}
+	if h := portBusyHint("tcp", "", errors.New("connection refused")); h != "" {
+		t.Fatalf("serial hint on a TCP link: %q", h)
+	}
+}
+
+// silentPort answers every read the way a serial port with nothing on the other
+// end does: no bytes, no error. bufio turns a run of those into ErrNoProgress.
+type silentPort struct{ writes int }
+
+func (s *silentPort) Read(p []byte) (int, error)  { return 0, nil }
+func (s *silentPort) Write(p []byte) (int, error) { s.writes++; return len(p), nil }
+func (s *silentPort) Close() error                { return nil }
+
+// A controller that never answers must fail ONCE, promptly, with a message that
+// says so — not wedge the poll loop for minutes inside bufio's retry budget.
+func TestSilentControllerFailsWithinTheReadTimeout(t *testing.T) {
+	c := New(Transport{Mode: "serial", COM: "COM_TEST", Baud: 9600})
+	c.conn = &silentPort{}
+	c.reader = bufio.NewReader(c.conn)
+
+	start := time.Now()
+	_, err := c.sendCommand(CMD_STATUS, nil)
+	elapsed := time.Since(start)
+
+	if err == nil {
+		t.Fatal("a silent controller reported success")
+	}
+	if elapsed > 3*ubReadTimeout {
+		t.Fatalf("took %s to give up — the read deadline is not bounding the exchange", elapsed.Round(time.Millisecond))
+	}
+	if !strings.Contains(err.Error(), "no reply") {
+		t.Fatalf("unhelpful error for a silent port: %v", err)
+	}
+}