ui: rename feed toggle to 'Signals only' / 'Show all'

The previous '🙈 Hide off-topic (232)' label was confusing — the emoji and
'off-topic' jargon didn't make the action obvious. Now a plain two-state
toggle: 'Signals only' (collapse non-crypto posts) ⇄ 'Show all'. Tooltip
still notes how many off-topic posts are hidden. Pure copy change — filter
logic untouched. Verified in browser: toggle collapses/restores correctly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/[locale]/trump/TrumpPageClient.tsx

@@ -127,7 +127,7 @@ export default function TrumpSignalPage({ initialPosts = null }: TrumpSignalPage
           {noiseCount > 0 && (
             <button
               onClick={() => { setHideNoise(v => !v); setPage(1) }}
-              title="Collapse posts the AI judged off-topic (not crypto-related)"
+              title={`Show only crypto-relevant posts — hides ${noiseCount} off-topic Trump posts`}
               style={{
                 padding: '4px 10px', borderRadius: 6,
                 border: '1px solid var(--line)',
@@ -137,7 +137,7 @@ export default function TrumpSignalPage({ initialPosts = null }: TrumpSignalPage
                 marginRight: 4,
               }}
             >
-              {hideNoise ? `✓ Off-topic hidden (${noiseCount})` : `🙈 Hide off-topic (${noiseCount})`}
+              {hideNoise ? 'Show all' : 'Signals only'}
             </button>
           )}
           <span style={{ fontSize: 11, color: 'var(--ink-4)', marginRight: 4 }}>