feat: follow the SUB VFO over OmniRig; distance column in the QSO grids

OmniRig reports the VFO pair (AA/AB/BA/BB) on the whole Yaesu range and never
the single-letter form. Only the latter was honoured, so every rig in that
family stayed pinned to VFO A: pressing SUB moved the radio but not OpsLog,
and a QSO worked on SUB was logged on the main VFO's frequency. The first
letter of the pair is the VFO being listened on — Log4OM reads it and gets the
right frequency on the same rigs, which is what showed the data was there.
The enum now wins over the Yaesu Freq==FreqB inference, which is only a
fallback for a rig file that names no VFO at all (the stock FTDX10 one answers
neither VS; nor FR; usably — verified on the air).

Split: the ON flag is still latched to survive a rig file that flips it on its
own, but the latch is now ARMED only after 8 flips in 30 s. A first cut at
3-in-15s was armed by the operator toggling split while testing, imposing the
6 s clearing delay on a radio that did not need it; a misreading file flips a
dozen times in that window untouched, so the two cases separate cleanly.

Distance (km) column added to Recent QSOs and Worked before (shared catalog).
Computed from the QSO's OWN my_grid/my_lat/lon first, falling back to the
current profile's locator: a log spans years and portable outings, so the
station a QSO was made from is not necessarily today's.

Locator: a precise QRZ/HamQTH grid is no longer overwritten by the cty.dat
entity centroid. The lookup runs several times per QSO and the provider gets
2 s; a slow second answer fell back to cty.dat and downgraded JN05JG to JN16
while name and QTH survived (they are only written when non-empty).

The OmniRig diagnostic line now logs what OpsLog concluded, not just what
OmniRig reported. icomnet.go: gofmt alignment only.

internal/cat/icomnet.go

@@ -98,8 +98,8 @@ type icomNet struct {
 	vTracked uint16
 	vCivSeq  uint16
 
-	rx       chan []byte   // CI-V byte chunks from civPump → Read (control replies)
-	scopeRx  chan []byte   // scope (0x27) frames, kept off rx so the panadapter
+	rx      chan []byte // CI-V byte chunks from civPump → Read (control replies)
+	scopeRx chan []byte // scope (0x27) frames, kept off rx so the panadapter
 	//                        stream can't crowd control replies out (→ ScopeChan)
 	leftover []byte        // partial chunk not yet returned by Read (Read-only)
 	readTO   time.Duration // Read timeout (SetReadTimeout)
@@ -114,11 +114,11 @@ type icomNet struct {
 	// login token every ~45 s. The rig invalidates the session ~2 min after login
 	// without renewal (this was the "loses control after 2 min" drop — RS-BA1/the
 	// Remote Utility renew too). Owned solely by ctrlPump after dial → no lock.
-	cTracked uint16             // control-stream tracked seq (continues after dial)
-	cAuthSeq uint16             // token-packet innerseq
-	cToken   uint32             // login token (opaque, echoed back verbatim)
-	cTokReq  uint16             // token-request id (echoed)
-	cSentBuf map[uint16][]byte  // control-stream retransmit buffer (token renewals)
+	cTracked uint16            // control-stream tracked seq (continues after dial)
+	cAuthSeq uint16            // token-packet innerseq
+	cToken   uint32            // login token (opaque, echoed back verbatim)
+	cTokReq  uint16            // token-request id (echoed)
+	cSentBuf map[uint16][]byte // control-stream retransmit buffer (token renewals)
 
 	// Receive-side retransmit (CI-V stream): track the rig's data-packet send seq
 	// and ask it to resend any gap. Under the scope stream, UDP drops are common;
@@ -844,8 +844,8 @@ func icnConnInfo(seq, innerSeq, tokReq uint16, sentid, rcvdid, token uint32, use
 	copy(b[0x60:0x70], icnPasscode(user))
 	b[0x70] = rxEnable // rxenable: 1 opens the 50003 RX audio stream, 0 = CI-V only
 	b[0x71] = 0x00     // txenable (Phase 5)
-	b[0x72] = 0x10 // rxcodec
-	b[0x73] = 0x04 // txcodec
+	b[0x72] = 0x10     // rxcodec
+	b[0x73] = 0x04     // txcodec
 	icnBE.PutUint32(b[0x74:], 16000)
 	icnBE.PutUint32(b[0x78:], 8000)
 	icnBE.PutUint32(b[0x7c:], uint32(civPort))