feat: symmetric audio bars + post-transcription hook

- PR cjpais#552: Symmetric mirrored audio bars visualization (25 buckets,
  150-2500Hz range, 13 bars with center-mirror effect)
- PR cjpais#930: Post-transcription hook support - runs hooks/transcription
  script from app data dir, passing text via stdin
- Overlay height adjusted for taller bars (34→40px CSS, 38→44px Rust)

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

Author: DylanBricar

src-tauri/src/actions.rs

@@ -740,6 +740,14 @@ impl ShortcutAction for TranscribeAction {
                             change_tray_icon(&ah, TrayIconState::Idle);
                         }
 
+                        // Run post-transcription hook if configured
+                        if !transcription.is_empty() {
+                            crate::managers::transcription::run_transcription_hook(
+                                &ah,
+                                &transcription,
+                            );
+                        }
+
                         // Always save to history for non-empty results or meaningful audio duration
                         if !transcription.is_empty() || duration_seconds > 1.0 {
                             let hm_clone = Arc::clone(&hm);

src-tauri/src/audio_toolkit/audio/recorder.rs

@@ -268,14 +268,14 @@ fn run_consumer(
     let mut recording = false;
 
     // ---------- spectrum visualisation setup ---------------------------- //
-    const BUCKETS: usize = 16;
+    const BUCKETS: usize = 25;
     const WINDOW_SIZE: usize = 512;
     let mut visualizer = AudioVisualiser::new(
         in_sample_rate,
         WINDOW_SIZE,
         BUCKETS,
-        400.0,  // vocal_min_hz
-        4000.0, // vocal_max_hz
+        150.0,  // vocal_min_hz
+        2500.0, // vocal_max_hz
     );
 
     fn handle_frame(

src-tauri/src/managers/transcription.rs

@@ -700,6 +700,72 @@ impl TranscriptionManager {
     }
 }
 
+/// Run a post-transcription hook script if it exists.
+/// Looks for `hooks/transcription` (or `.exe`/`.bat`/`.cmd` on Windows)
+/// in the app data directory and runs it, passing the transcription text via stdin.
+pub fn run_transcription_hook(app_handle: &AppHandle, text: &str) {
+    use tauri::Manager;
+
+    let data_dir = match app_handle.path().app_data_dir() {
+        Ok(d) => d,
+        Err(_) => return,
+    };
+
+    let hook_path = data_dir.join("hooks").join("transcription");
+
+    // On Windows, also check for .exe, .bat, .cmd
+    #[cfg(target_os = "windows")]
+    let hook_path = {
+        if hook_path.exists() {
+            hook_path
+        } else {
+            let extensions = ["exe", "bat", "cmd"];
+            extensions
+                .iter()
+                .map(|ext| hook_path.with_extension(ext))
+                .find(|p| p.exists())
+                .unwrap_or(hook_path)
+        }
+    };
+
+    if !hook_path.exists() {
+        return;
+    }
+
+    let text = text.to_string();
+    let hook = hook_path.clone();
+    std::thread::spawn(move || {
+        use std::io::Write;
+        use std::process::{Command, Stdio};
+
+        let mut child = match Command::new(&hook)
+            .stdin(Stdio::piped())
+            .stdout(Stdio::null())
+            .stderr(Stdio::null())
+            .spawn()
+        {
+            Ok(c) => c,
+            Err(e) => {
+                warn!("Failed to run transcription hook {:?}: {}", hook, e);
+                return;
+            }
+        };
+
+        if let Some(mut stdin) = child.stdin.take() {
+            let _ = stdin.write_all(text.as_bytes());
+        }
+
+        match child.wait() {
+            Ok(status) => {
+                if !status.success() {
+                    warn!("Transcription hook exited with status: {}", status);
+                }
+            }
+            Err(e) => warn!("Failed to wait for transcription hook: {}", e),
+        }
+    });
+}
+
 impl Drop for TranscriptionManager {
     fn drop(&mut self) {
         debug!("Shutting down TranscriptionManager");

src-tauri/src/overlay.rs

@@ -31,7 +31,7 @@ tauri_panel! {
 }
 
 const OVERLAY_WIDTH: f64 = 210.0;
-const OVERLAY_HEIGHT: f64 = 38.0;
+const OVERLAY_HEIGHT: f64 = 44.0;
 
 #[cfg(target_os = "macos")]
 const OVERLAY_TOP_OFFSET: f64 = 46.0;

src/overlay/RecordingOverlay.css

@@ -1,5 +1,5 @@
 .recording-overlay {
-  height: 34px;
+  height: 40px;
   width: 200px;
   display: flex;
   align-items: center;
@@ -76,17 +76,17 @@
 .bars-container {
   display: flex;
   align-items: center;
-  gap: 3px;
-  height: 24px;
+  gap: 1.5px;
+  height: 28px;
   flex: 1;
 }
 
 .bar {
   flex: 1;
   background: rgba(255, 255, 255, 0.6);
-  max-height: 22px;
-  border-radius: 1.5px;
-  min-height: 3px;
+  max-height: 26px;
+  border-radius: 1px;
+  min-height: 2px;
   transition:
     height 60ms ease-out,
     opacity 80ms ease-out;

src/overlay/RecordingOverlay.tsx

@@ -121,9 +121,11 @@ const TimerDisplay: React.FC<{ startTime: number; isPaused: boolean }> = ({
   return <div className="timer-text">{display}</div>;
 };
 
+const NUM_BARS = 13;
+
 const AudioBars: React.FC = () => {
   const barsRef = useRef<HTMLDivElement>(null);
-  const smoothedRef = useRef<number[]>(Array(16).fill(0));
+  const smoothedRef = useRef<number[]>(Array(25).fill(0));
 
   useEffect(() => {
     let unlisten: (() => void) | null = null;
@@ -138,11 +140,14 @@ const AudioBars: React.FC = () => {
 
         if (barsRef.current) {
           const bars = barsRef.current.children;
-          for (let i = 0; i < bars.length; i++) {
-            const v = smoothed[i] || 0;
+          const half = Math.ceil(NUM_BARS / 2);
+          for (let i = 0; i < NUM_BARS; i++) {
+            // Mirror: map bar index to bucket index (center = highest bucket)
+            const bucketIdx = i < half ? i : NUM_BARS - 1 - i;
+            const v = smoothed[bucketIdx] || 0;
             const el = bars[i] as HTMLElement;
-            el.style.height = `${Math.min(20, 3 + Math.pow(v, 0.6) * 17)}px`;
-            el.style.opacity = `${Math.max(0.25, v * 1.4)}`;
+            el.style.height = `${Math.min(24, 2 + Math.pow(v, 0.6) * 22)}px`;
+            el.style.opacity = `${Math.max(0.2, v * 1.4)}`;
           }
         }
       });
@@ -155,7 +160,7 @@ const AudioBars: React.FC = () => {
 
   return (
     <div className="bars-container" ref={barsRef}>
-      {Array.from({ length: 9 }, (_, i) => (
+      {Array.from({ length: NUM_BARS }, (_, i) => (
         <div key={i} className="bar" />
       ))}
     </div>