Add sync mode to prevent mining during sidechain load

- Added m_readyToMine flag to SideChain
- Display LOADING SIDECHAIN banner at startup
- Delay stratum server and mining until sidechain sync completes
- Display MINING IS NOW ENABLED when ready
- Prevents premature mining that caused peer bans and chain splits

P2PServer starts immediately for sync, but stratum port doesn't
open until sidechain is fully loaded and after pruning completes

src/p2pool.cpp

@@ -1417,6 +1417,17 @@ void p2pool::download_block_headers4(uint64_t start_height, uint64_t current_hei
 				update_median_timestamp();
 				if (m_serversStarted.exchange(1) == 0) {
 					m_p2pServer = new P2PServer(this);
+                                        
+                                        // Display loading banner
+                                        LOGINFO(0, log::LightCyan() << "########################################################");
+                                        LOGINFO(0, log::LightCyan() << "LOADING SIDECHAIN - MINING MAY NOT OCCUR UNTIL COMPLETE");
+                                        LOGINFO(0, log::LightCyan() << "########################################################");
+                                        
+                                        // Wait for sidechain to be ready before starting stratum/mining
+                                        while (!m_sideChain->is_ready_to_mine()) {
+                                                std::this_thread::sleep_for(std::chrono::seconds(5));
+                                        }
+                                        
 					m_stratumServer = new StratumServer(this);
 #if defined(WITH_RANDOMX) && !defined(P2POOL_UNIT_TESTS)
 					if (m_params->m_minerThreads) {

src/side_chain.cpp

@@ -2447,6 +2447,15 @@ void SideChain::prune_old_blocks()
 		}
 #endif
 	}
+
+        // If side-chain started pruning blocks it means the initial sync is complete
+        // It's now safe to delete cached blocks
+        if (!m_readyToMine.load()) {
+                m_readyToMine.store(true);
+                LOGINFO(0, log::LightGreen() << "########################################");
+                LOGINFO(0, log::LightGreen() << "SIDECHAIN LOADED - MINING IS NOW ENABLED");
+                LOGINFO(0, log::LightGreen() << "########################################");
+        }
 }
 
 void SideChain::get_missing_blocks(unordered_set<hash>& missing_blocks) const

src/side_chain.h

@@ -88,6 +88,8 @@ public:
 	[[nodiscard]] FORCEINLINE uint64_t miner_count() const { ReadLock lock(m_seenDataLock); return m_seenWallets.size(); }
 	[[nodiscard]] FORCEINLINE uint64_t onion_pubkeys_count() const { ReadLock lock(m_seenDataLock); return m_seenOnionPubkeys.size(); }
 	[[nodiscard]] uint64_t last_updated() const;
+        [[nodiscard]] bool is_ready_to_mine() const { return m_readyToMine.load(); }
+        void set_ready_to_mine(bool ready) { m_readyToMine.store(ready); }
 	[[nodiscard]] bool is_default() const;
 	[[nodiscard]] bool is_mini() const;
 	[[nodiscard]] bool is_nano() const;
@@ -141,6 +143,9 @@ private:
 	mutable uint64_t m_adoptedGenesisHeight{ 0 };
         mutable uint64_t m_adoptedGenesisTime{ 0 };
 
+      	// Sync state - prevents mining/bans during startup
+	std::atomic<bool> m_readyToMine{ false };
+
 	std::map<uint64_t, std::vector<PoolBlock*>> m_blocksByHeight;
 	unordered_map<hash, PoolBlock*> m_blocksById;
 	unordered_map<root_hash, PoolBlock*> m_blocksByMerkleRoot;