Optimize BLE mesh network for robustness and range (#314)

- Fixed relay probability calculation for 2-node networks (0% relay needed)
- Added protocol ACKs to prevent unnecessary retransmissions
- Implemented MessageState for enhanced duplicate detection
- Added exponential backoff for collision avoidance
- Fixed duplicate sends for bidirectional connections
- Resolved packet ID generation issues using immutable fields only
- Implemented smart rate limiting with progressive throttling
- Removed unnecessary debug logging and fixed build warnings
- Optimized message routing to prevent flooding in small networks

Co-authored-by: jack <jackjackbits@users.noreply.github.com>

bitchatTests/TestUtilities/TestHelpers.swift

@@ -55,7 +55,8 @@ class TestHelpers {
         recipientID: String? = nil,
         payload: Data = "test payload".data(using: .utf8)!,
         signature: Data? = nil,
-        ttl: UInt8 = 3
+        ttl: UInt8 = 3,
+        sequenceNumber: UInt32 = 1
     ) -> BitchatPacket {
         return BitchatPacket(
             type: type,
@@ -64,7 +65,8 @@ class TestHelpers {
             timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
             payload: payload,
             signature: signature,
-            ttl: ttl
+            ttl: ttl,
+            sequenceNumber: sequenceNumber
         )
     }