fix: remaining LOTUS_BUGS.md items — hardcoded hex and a11y

- GifPicker: replace #FF6B00 and #060c14 with var(--lt-accent-orange) and
  var(--lt-bg-secondary); rgba opacity values use color-mix()
- VoiceMessageRecorder: replace #FF6B00 and #00FF88 waveform/dot colors
  with var(--lt-accent-orange) / var(--lt-accent-green)
- Presence: replace aria-labelledby referencing a lazy tooltip ID with a
  direct aria-label so screen readers always have the text in the DOM

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

src/app/components/VoiceMessageRecorder.tsx

@@ -203,7 +203,7 @@ export function VoiceMessageRecorder({ onSend, onError }: VoiceRecorderProps) {
             width: toRem(8),
             height: toRem(8),
             borderRadius: '50%',
-            background: lotusTerminal ? '#FF6B00' : 'var(--tc-danger-normal)',
+            background: lotusTerminal ? 'var(--lt-accent-orange)' : 'var(--tc-danger-normal)',
             flexShrink: 0,
             animation: 'pttLivePulse 900ms ease-in-out infinite',
           }}
@@ -214,7 +214,7 @@ export function VoiceMessageRecorder({ onSend, onError }: VoiceRecorderProps) {
             minWidth: toRem(32),
             fontVariantNumeric: 'tabular-nums',
             ...(lotusTerminal
-              ? { fontFamily: 'JetBrains Mono, monospace', color: '#00FF88', fontWeight: 700 }
+              ? { fontFamily: 'JetBrains Mono, monospace', color: 'var(--lt-accent-green)', fontWeight: 700 }
               : {}),
           }}
         >
@@ -233,7 +233,7 @@ export function VoiceMessageRecorder({ onSend, onError }: VoiceRecorderProps) {
                 width: toRem(2),
                 height: toRem(2 + (h / barMax) * 16),
                 borderRadius: toRem(1),
-                background: lotusTerminal ? '#00FF88' : 'var(--tc-primary-normal)',
+                background: lotusTerminal ? 'var(--lt-accent-green)' : 'var(--tc-primary-normal)',
                 flexShrink: 0,
               }}
             />