Add download all recordings as ZIP feature

- Add /download_all endpoint to create in-memory ZIP archive
- Include zipfile and io imports for ZIP creation
- Add "Download All as ZIP" button in web interface (only shows when recordings exist)
- ZIP filename includes timestamp: wedding_recordings_YYYYMMDD_HHMMSS.zip
- Only includes .wav files from recordings directory
- Update API documentation in README.md
- Document feature in CLAUDE.md

Allows users to quickly backup all guest recordings in a single download.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

rotary_phone_web.py

@@ -19,6 +19,8 @@ import json
 import sys
 import zlib
 import shutil
+import zipfile
+import io
 
 # Load configuration
 def load_system_config():
@@ -798,6 +800,42 @@ def download_recording(filename):
         return send_file(filepath, as_attachment=True)
     return "File not found", 404
 
+@app.route('/download_all')
+def download_all_recordings():
+    """Download all recordings as a ZIP file"""
+    if not os.path.exists(OUTPUT_DIR):
+        return "No recordings found", 404
+
+    # Get all recording files
+    recordings = [f for f in os.listdir(OUTPUT_DIR)
+                  if f.endswith('.wav') and os.path.isfile(os.path.join(OUTPUT_DIR, f))]
+
+    if not recordings:
+        return "No recordings found", 404
+
+    # Create ZIP file in memory
+    memory_file = io.BytesIO()
+
+    with zipfile.ZipFile(memory_file, 'w', zipfile.ZIP_DEFLATED) as zf:
+        for filename in recordings:
+            filepath = os.path.join(OUTPUT_DIR, filename)
+            # Add file to ZIP with just the filename (no path)
+            zf.write(filepath, arcname=filename)
+
+    # Seek to beginning of file
+    memory_file.seek(0)
+
+    # Generate filename with timestamp
+    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
+    zip_filename = f"wedding_recordings_{timestamp}.zip"
+
+    return send_file(
+        memory_file,
+        mimetype='application/zip',
+        as_attachment=True,
+        download_name=zip_filename
+    )
+
 @app.route('/delete/<filename>', methods=['POST'])
 def delete_recording(filename):
     """Delete a recording"""
@@ -1499,8 +1537,15 @@ def main():
 
         <!-- Recordings Card -->
         <div class="card">
-            <h2>🎙️ Recordings</h2>
-            
+            <div style="display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px;">
+                <h2 style="margin: 0;">🎙️ Recordings</h2>
+                {% if recordings %}
+                <button class="btn btn-primary" onclick="downloadAllRecordings()" style="font-size: 0.9em;">
+                    📦 Download All as ZIP
+                </button>
+                {% endif %}
+            </div>
+
             {% if recordings %}
             <div class="stats">
                 <div class="stat-box">
@@ -1715,7 +1760,11 @@ def main():
         function downloadRecording(filename) {
             window.location.href = '/download/' + filename;
         }
-        
+
+        function downloadAllRecordings() {
+            window.location.href = '/download_all';
+        }
+
         function deleteRecording(filename, index) {
             if (confirm('Delete this recording?')) {
                 fetch('/delete/' + filename, { method: 'POST' })