CBL-5396: Use os_log instead of NSLog for Console Log

Objective-C/CBLConsoleLogger.m

@@ -25,6 +25,7 @@ @implementation CBLConsoleLogger
 @synthesize level=_level, domains=_domains;
 
 static NSMutableDictionary<NSNumber *, os_log_t>* osLogDictionary;
+static os_log_t logger;
 
 - (instancetype) initWithLogLevel: (CBLLogLevel)level {
     self = [super init];
@@ -79,4 +80,17 @@ - (void) initializeOSLogDomains {
     osLogDictionary[@(kCBLLogDomainListener)] = os_log_create("com.couchbase.lite.ios", "Listener");
     #endif
 }
+
++ (os_log_t) internalLogger {
+    if(!logger){
+        logger = os_log_create("com.couchbase.lite.ios", "Log");
+    }
+    return logger;
+}
+
++ (void) logWithInternal: (NSString*)message {
+    logger = [self internalLogger];
+    os_log(logger, "%@", message);
+}
+
 @end

Objective-C/CBLDatabase.mm

@@ -114,8 +114,7 @@ to be done in CBLInit()which is called only once when the first CBLDatabase is c
  */
 + (void) initialize {
     if (self == [CBLDatabase class]) {
-        os_log_t logger = os_log_create("com.couchbase.lite.ios", "UserAgent");
-        os_log(logger, "%@", [CBLVersion userAgent]);
+        [CBLConsoleLogger logWithInternal:[CBLVersion userAgent]];
         // Initialize logging
         CBLAssertNotNil(CBLLog.sharedInstance);
     }

Objective-C/CBLLog.mm

@@ -155,12 +155,12 @@ - (instancetype) initWithDefault {
 #ifdef DEBUG
         // Check if user overrides the default callback log level:
         NSString* userLogLevel = [NSUserDefaults.standardUserDefaults objectForKey: @"CBLLogLevel"];
-        oslogger = os_log_create("com.couchbase.lite.ios", "DebugBuild");
         if (userLogLevel) {
             callbackLogLevel = string2level(userLogLevel);
         }
         if (callbackLogLevel != kC4LogWarning) {
-            os_log(oslogger, "CouchbaseLite minimum log level is %s", kLevelNames[callbackLogLevel]);
+            NSString* message = [NSString stringWithFormat: @"CouchbaseLite minimum log level is %s", kLevelNames[callbackLogLevel]];
+            [CBLConsoleLogger logWithInternal: message];
         }
 #endif
 

Objective-C/Internal/CBLLog+Internal.h

@@ -36,6 +36,10 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (instancetype) initWithLogLevel: (CBLLogLevel)level;
 
++ (os_log_t) internalLogger;
+
++ (void) logWithInternal: (nonnull NSString*)message;
+
 @end
 
 @interface CBLFileLogger ()