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
-            publish a transmit power reading, so a PWR bar here would be an
-            empty promise. */}
+        {/* Meters. The S-meter while receiving, power and SWR while
+            transmitting — the radio answers TX_POWER and TX_SWR only when it is
+            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 */}