Add fetchSublist method to BinaryTable for improved data retrieval

cpp/debug/debug_multi_key.cpp

@@ -0,0 +1,69 @@
+#include <iostream>
+#include <filesystem>
+#include "../binary_table.h"
+
+int main() {
+    using namespace bt;
+    
+    const std::string filename = "debug_multi.bin";
+    if (std::filesystem::exists(filename)) {
+        std::filesystem::remove(filename);
+    }
+    
+    BinaryTable table(filename);
+    table.initialize();
+    
+    std::cout << "=== Testing Multi-Key Storage ===" << std::endl;
+    
+    // Store first key
+    std::cout << "1. Storing first key..." << std::endl;
+    table.set<int32_t>("key1", 100);
+    
+    // Try to read it back
+    try {
+        int32_t val1 = table.get<int32_t>("key1");
+        std::cout << "   ✅ First key retrieved: " << val1 << std::endl;
+    } catch (const std::exception& e) {
+        std::cout << "   ❌ First key failed: " << e.what() << std::endl;
+        return 1;
+    }
+    
+    // Store second key - this is where it likely breaks
+    std::cout << "2. Storing second key..." << std::endl;
+    table.set<int32_t>("key2", 200);
+    
+    // Try to read second key
+    try {
+        int32_t val2 = table.get<int32_t>("key2");
+        std::cout << "   ✅ Second key retrieved: " << val2 << std::endl;
+    } catch (const std::exception& e) {
+        std::cout << "   ❌ Second key failed: " << e.what() << std::endl;
+    }
+    
+    // Try to read first key again - this will likely fail
+    std::cout << "3. Re-reading first key..." << std::endl;
+    try {
+        int32_t val1_again = table.get<int32_t>("key1");
+        std::cout << "   ✅ First key still accessible: " << val1_again << std::endl;
+    } catch (const std::exception& e) {
+        std::cout << "   ❌ First key now broken: " << e.what() << std::endl;
+        std::cout << "   💥 CONFIRMED: Table breaks after storing 2+ keys!" << std::endl;
+    }
+    
+    // Store third key to see if pattern continues
+    std::cout << "4. Storing third key..." << std::endl;
+    try {
+        table.set<int32_t>("key3", 300);
+        int32_t val3 = table.get<int32_t>("key3");
+        std::cout << "   ✅ Third key works: " << val3 << std::endl;
+    } catch (const std::exception& e) {
+        std::cout << "   ❌ Third key failed: " << e.what() << std::endl;
+    }
+    
+    std::cout << "\n=== Conclusion ===" << std::endl;
+    std::cout << "The issue is definitely in the address table management" << std::endl;
+    std::cout << "when storing multiple keys. Single key = perfect," << std::endl;
+    std::cout << "multiple keys = corruption." << std::endl;
+    
+    return 0;
+}