feat(email): send attachments as WhatsApp documents, fix forward sender

- Add /send-document endpoint to WhatsApp bridge (base64 document send)
- save_email_as_note() now saves attachment files to disk alongside note
- email_digest: extract original sender for Fwd: emails so header shows
  the real author, not the forwarder; send attachment files after summary
- email_forward: send attachment files as documents after text parts
- Add extract_original_sender() and save_email_attachment_files() helpers

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

tools/email_process.py

@@ -93,6 +93,46 @@ def get_email_attachments(msg) -> list:
             attachments.append(f"[{part.get_content_type()}]")
     return attachments
 
+def save_email_attachment_files(msg, dest_dir: Path) -> list:
+    """Save attachment files from email to dest_dir. Returns list of saved file paths."""
+    saved = []
+    if not msg.is_multipart():
+        return saved
+    dest_dir.mkdir(parents=True, exist_ok=True)
+    for part in msg.walk():
+        filename = part.get_filename()
+        if not filename:
+            continue
+        filename = decode_mime_header(filename)
+        payload = part.get_payload(decode=True)
+        if payload is None:
+            continue
+        dest = dest_dir / filename
+        # Avoid overwriting — append counter if needed
+        counter = 1
+        while dest.exists():
+            stem, suffix = Path(filename).stem, Path(filename).suffix
+            dest = dest_dir / f"{stem}_{counter}{suffix}"
+            counter += 1
+        dest.write_bytes(payload)
+        saved.append(dest)
+    return saved
+
+def extract_original_sender(subject: str, body_content: str, from_full: str) -> str:
+    """If email is a forward, extract original sender from body."""
+    if not re.match(r'^(fwd?|fw)\s*[:\s]', subject, re.IGNORECASE):
+        return from_full
+    match = re.search(
+        r'(?:De la|From):\s*(.+?)(?:\n|$)',
+        body_content, re.IGNORECASE | re.MULTILINE
+    )
+    if match:
+        candidate = match.group(1).strip()
+        # Skip blank or markdown artifacts
+        if candidate and not candidate.startswith('**') and '@' in candidate or len(candidate) > 3:
+            return candidate
+    return from_full
+
 def extract_sender_email(from_header: str) -> str:
     """Extract just the email address from From header"""
     match = re.search(r'<([^>]+)>', from_header)
@@ -204,11 +244,15 @@ def save_email_as_note(eid: str) -> dict:
     
     KB_PATH.mkdir(parents=True, exist_ok=True)
     filepath.write_text(content, encoding='utf-8')
-    
+
+    # Save attachment files next to the note
+    att_dir = KB_PATH / f"{date_prefix}_{slug}_attachments"
+    attachment_paths = save_email_attachment_files(msg, att_dir)
+
     # Mark as seen
     mail.store(eid.encode(), '+FLAGS', '\\Seen')
     mail.logout()
-    
+
     return {
         'ok': True,
         'file': str(filepath),
@@ -216,6 +260,7 @@ def save_email_as_note(eid: str) -> dict:
         'from': sender_email,
         'from_full': from_addr,
         'date': date_str,
+        'attachment_paths': [str(p) for p in attachment_paths],
     }
 
 def save_unread_emails():