debug(contacts): Add detailed logging to diagnose last_seen matching issue

Add comprehensive debug logging to trace last_seen data flow:

cli.py (get_contacts_with_last_seen):
- Log apply_to command success/failure with error details
- Log number of bytes returned by command
- Log number of contacts parsed from JSON
- Log sample contact with public_key prefix and last_advert value
- Log raw output on JSON parse errors

api.py (get_contacts_detailed_api):
- Log number of detailed contacts retrieved
- Log number of matched contacts after merging
- Fix case sensitivity: normalize both prefix and full_key to lowercase

This will help identify why all contacts show "Last seen: Unknown".

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

app/meshcore/cli.py

@@ -553,27 +553,37 @@ def get_contacts_with_last_seen() -> Tuple[bool, Dict[str, Dict], str]:
         success, stdout, stderr = _run_command(['apply_to', 't=1,t=2,t=3,t=4', 'contact_info'])
 
         if not success:
+            logger.error(f"apply_to contact_info failed: {stderr}")
             return False, {}, stderr or 'Failed to get contact details'
 
+        logger.info(f"apply_to contact_info returned {len(stdout)} bytes")
+
         # Parse JSON output
         try:
             # The output should be a JSON array
             contact_list = json.loads(stdout)
 
             if not isinstance(contact_list, list):
+                logger.error(f"Unexpected response type: {type(contact_list)}")
                 return False, {}, 'Unexpected response format (expected JSON array)'
 
+            logger.info(f"Parsed {len(contact_list)} contacts from JSON")
+
             # Build dictionary indexed by public_key for easy lookup
             contacts_dict = {}
             for contact in contact_list:
                 if 'public_key' in contact:
                     # Use full public key as index
                     contacts_dict[contact['public_key']] = contact
+                    # Log first contact for debugging
+                    if len(contacts_dict) == 1:
+                        logger.info(f"Sample contact: public_key={contact['public_key'][:12]}..., last_advert={contact.get('last_advert', 'MISSING')}")
 
             return True, contacts_dict, ""
 
         except json.JSONDecodeError as e:
             logger.error(f"Failed to parse contact_info JSON: {e}")
+            logger.error(f"Raw output (first 500 chars): {stdout[:500]}")
             return False, {}, f'JSON parse error: {str(e)}'
 
     except Exception as e:

app/routes/api.py

@@ -1245,17 +1245,23 @@ def get_contacts_detailed_api():
         success_detailed, contacts_detailed, error_detailed = cli.get_contacts_with_last_seen()
 
         if success_detailed:
+            logger.info(f"Got {len(contacts_detailed)} detailed contacts")
+
             # Merge last_advert data with contacts
             # Match by public_key_prefix (first 12 chars of full public_key)
+            matched_count = 0
             for contact in contacts:
-                prefix = contact.get('public_key_prefix', '')
+                prefix = contact.get('public_key_prefix', '').lower()
 
                 # Find matching contact in detailed data
                 for full_key, details in contacts_detailed.items():
-                    if full_key.startswith(prefix):
+                    if full_key.lower().startswith(prefix):
                         # Add last_seen timestamp
                         contact['last_seen'] = details.get('last_advert', None)
+                        matched_count += 1
                         break
+
+            logger.info(f"Matched {matched_count} out of {len(contacts)} contacts with last_seen data")
         else:
             # If detailed fetch failed, log warning but still return contacts without last_seen
             logger.warning(f"Failed to get last_seen data: {error_detailed}")