feat(tci): the transmit meters, and no temperature invented

TX_POWER and TX_SWR are read-only commands the radio answers when asked,
so they are asked for on each poll of a KEYED radio and not at all
otherwise: a receiving station pays nothing for meters nobody is watching.
Both appear next to the S-meter only while transmitting, because showing
them the rest of the time would show the last thing that happened as if it
were now.

An SWR of 0 draws as '—' rather than as 1.0. A perfect match on an antenna
nobody has measured is the one reading an operator should never be handed.

There is no temperature. The protocol's command list has TX_POWER and
TX_SWR and nothing thermal at all — so rather than leave the question
hanging, it is written down where the next person will look for it. A
temperature invented from something else, on a transmitter, is exactly the
kind of number somebody would trust.

frontend/src/components/TCIPanel.tsx

@@ -23,6 +23,7 @@ type TCIState = {
   filter_lo: number; filter_hi: number;
   rit: boolean; rit_offset: number; xit: boolean; xit_offset: number; lock: boolean; split: boolean;
   smeter: number; modulations?: string[];
+  tx_power_w: number; tx_swr: number;
 };
 
 const ZERO: TCIState = {
@@ -30,6 +31,7 @@ const ZERO: TCIState = {
   volume: 0, mute: false, squelch_on: false, squelch: 0,
   nb: false, nr: false, anf: false, apf: false, filter_lo: 0, filter_hi: 0,
   rit: false, rit_offset: 0, xit: false, xit_offset: 0, lock: false, split: false, smeter: 0,
+  tx_power_w: 0, tx_swr: 0,
 };
 
 // The widths worth a button, PER MODE — because 250 Hz is useless in SSB and
@@ -265,9 +267,12 @@ export function TCIPanel({ onReportRST }: { onReportRST?: (rst: string) => void
         {off && <div className="text-xs text-muted-foreground px-1">{t('tcip.waiting')}</div>}
         {!!err && <div className="text-[11px] text-danger px-1">{err}</div>}
 
-        {/* Meters — one for now: TCI reports the receive level and does not
+        {/* Meters. The S-meter while receiving, power and SWR while
-            publish a transmit power reading, so a PWR bar here would be an
+            transmitting — the radio answers TX_POWER and TX_SWR only when it is
-            empty promise. */}
+            keyed, so showing them the rest of the time would be showing the
+            last thing that happened as if it were now.
+            There is no temperature: the protocol has no such command, and a
+            made-up figure on a transmitter is the kind somebody trusts. */}
         <Card icon={Activity} title={t('tcip.meters')}>
           <MeterBar label="S-METER" value={st.tx ? 0 : sBar(st.smeter)} lo={0} hi={100}
             accent="#16a34a" segColor={sSegColor}
@@ -277,6 +282,18 @@ export function TCIPanel({ onReportRST }: { onReportRST?: (rst: string) => void
               onReportRST(sMeterRST(s.s, s.over, mode));
             }}
             title={t('tcip.sMeterHint')} />
+          {st.tx && (
+            <div className="grid grid-cols-1 sm:grid-cols-2 gap-2">
+              <MeterBar label="PWR" value={st.tx_power_w} lo={0} hi={Math.max(10, Math.ceil(st.tx_power_w / 10) * 10)}
+                accent="#0ea5e9" display={`${st.tx_power_w.toFixed(1)} W`} />
+              {/* 0 is "not measured yet", and it must not draw as a perfect
+                  match: an SWR of 1.0 on an antenna nobody has measured is the
+                  one reading an operator should not be handed. */}
+              <MeterBar label="SWR" value={st.tx_swr > 0 ? Math.min(100, (st.tx_swr - 1) * 50) : 0} lo={0} hi={100}
+                accent="#f59e0b" display={st.tx_swr > 0 ? st.tx_swr.toFixed(1) : '—'}
+                segColor={(f) => (f > 0.5 ? '#dc2626' : f > 0.25 ? '#f59e0b' : '#16a34a')} />
+            </div>
+          )}
         </Card>
 
         {/* Transmit */}

frontend/wailsjs/go/models.ts

@@ -1238,6 +1238,8 @@ export namespace cat {
 	    lock: boolean;
 	    split: boolean;
 	    smeter: number;
+	    tx_power_w: number;
+	    tx_swr: number;
 	    modulations?: string[];
 	
 	    static createFrom(source: any = {}) {
@@ -1273,6 +1275,8 @@ export namespace cat {
 	        this.lock = source["lock"];
 	        this.split = source["split"];
 	        this.smeter = source["smeter"];
+	        this.tx_power_w = source["tx_power_w"];
+	        this.tx_swr = source["tx_swr"];
 	        this.modulations = source["modulations"];
 	    }
 	}

internal/cat/tci.go

@@ -304,6 +304,18 @@ func (t *TCI) ReadState() (RigState, error) {
 	} else {
 		st.FreqHz = t.freqA
 	}
+	// The transmit meters are asked for, not pushed: TX_POWER and TX_SWR are
+	// read-only commands the radio answers when asked, and asking is only worth
+	// anything while it is keyed. Fired and forgotten from here — the answers
+	// arrive on the reader like everything else — and only while transmitting,
+	// so a receiving station pays nothing for a meter nobody is watching.
+	if t.tx {
+		tx := t
+		go func() {
+			_ = tx.send("tx_power;")
+			_ = tx.send("tx_swr;")
+		}()
+	}
 	st.Mode = tciModeToADIF(t.mode, t.digitalDefault)
 	if st.FreqHz > 0 {
 		st.Band = BandFromHz(st.FreqHz)

internal/cat/tci_panel.go

@@ -68,6 +68,17 @@ type TCIPanelState struct {
 	// several times a second while receiving.
 	SMeter int `json:"smeter"`
 
+	// TXPowerW and TXSWR are the transmit meters. READ-ONLY in TCI, and only
+	// answered while transmitting — asked for on every poll of a keyed radio,
+	// see ReadState.
+	//
+	// There is no temperature in this protocol. The command list has TX_POWER
+	// and TX_SWR and nothing thermal at all, so a temperature reading here would
+	// have to be invented, and an invented temperature on a transmitter is the
+	// kind of number somebody trusts.
+	TXPowerW float64 `json:"tx_power_w"`
+	TXSWR    float64 `json:"tx_swr"`
+
 	// Modulations is what this radio will accept, straight from its own
 	// announcement, so the mode buttons are the radio's and not a guess.
 	Modulations []string `json:"modulations,omitempty"`
@@ -194,6 +205,14 @@ func (t *TCI) handlePanel(name string, get func(int) string, args string) bool {
 		if forRX0() {
 			p.Lock = yes(get(1))
 		}
+	case "tx_power":
+		if v, err := strconv.ParseFloat(strings.TrimSpace(get(0)), 64); err == nil {
+			p.TXPowerW = v
+		}
+	case "tx_swr":
+		if v, err := strconv.ParseFloat(strings.TrimSpace(get(0)), 64); err == nil {
+			p.TXSWR = v
+		}
 	case "rx_smeter":
 		if n, ok := num(get(1)); ok && forRX0() {
 			p.SMeter = n