Apply black code formatting

Formatted Python code using black for:
- crypto_clients.py
- crypto_watcher.py
- test_crypto_watcher.py

Maintains consistent code style across the codebase.

debug_auth_headers.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+"""
+Debug script to examine the exact WWW-Authenticate header
+that Monero wallet RPC sends and how urllib handles it.
+"""
+import urllib.request
+import urllib.error
+import json
+
+def examine_auth_challenge():
+    """Look at the WWW-Authenticate header from the server"""
+    print("=== Examining Authentication Challenge ===")
+    
+    rpc_url = "http://127.0.0.1:18083/json_rpc"
+    payload = {"jsonrpc": "2.0", "id": 1, "method": "get_height"}
+    data = json.dumps(payload).encode()
+    
+    # Make request without auth to get the challenge
+    req = urllib.request.Request(rpc_url, data=data, 
+                               headers={"Content-Type": "application/json"})
+    
+    try:
+        with urllib.request.urlopen(req) as resp:
+            print("Unexpected: No auth required")
+            return None
+    except urllib.error.HTTPError as e:
+        if e.code == 401:
+            www_auth = e.headers.get('WWW-Authenticate', '')
+            print(f"WWW-Authenticate header: {www_auth!r}")
+            
+            # Parse it
+            if www_auth.startswith('Digest '):
+                challenge = www_auth[7:].strip()
+                print(f"Challenge details: {challenge}")
+                
+                # Parse individual components
+                import re
+                pattern = r'(\w+)=(?:"([^"]*)"|([^,\s]+))'
+                matches = re.findall(pattern, challenge)
+                
+                print("Parsed components:")
+                for key, quoted_val, unquoted_val in matches:
+                    val = quoted_val if quoted_val else unquoted_val
+                    print(f"  {key} = {val!r}")
+                    
+                return dict((key, quoted_val if quoted_val else unquoted_val) 
+                           for key, quoted_val, unquoted_val in matches)
+            else:
+                print(f"Not Digest auth: {www_auth}")
+                return None
+        else:
+            print(f"Unexpected error: {e.code} {e.reason}")
+            return None
+
+if __name__ == "__main__":
+    challenge = examine_auth_challenge()
+    
+    if challenge:
+        print()
+        print("=== Analysis ===")
+        print(f"Realm: {challenge.get('realm', 'NOT SET')}")
+        print(f"Nonce: {challenge.get('nonce', 'NOT SET')}")  
+        print(f"QOP: {challenge.get('qop', 'NOT SET')}")
+        print(f"Algorithm: {challenge.get('algorithm', 'NOT SET (defaults to MD5)')}")
+        
+        # Check for any unusual parameters
+        standard_params = {'realm', 'nonce', 'qop', 'algorithm', 'opaque'}
+        extra_params = set(challenge.keys()) - standard_params
+        if extra_params:
+            print(f"Extra parameters: {extra_params}")