Use coins_plm.py as single source of truth for ElectrumX patch

- Remove inline Palladium coin definition from Dockerfile.electrumx
  and COPY coins_plm.py instead, reducing duplication
- Add TX_COUNT/TX_COUNT_HEIGHT/TX_PER_BLOCK to coins_plm.py with
  real chain data (457478 txs at height 382404)
- Update entrypoint.sh to fetch live TX stats from palladiumd at
  container startup, keeping sync estimates accurate automatically

electrumx-patch/coins_plm.py

@@ -21,6 +21,11 @@ class Palladium(Bitcoin):
     # Since we share Genesis with Bitcoin, we must clear inherited checkpoints
     CHECKPOINTS = []
 
+    # === Network statistics (required by ElectrumX) ===
+    TX_COUNT = 457478
+    TX_COUNT_HEIGHT = 382404
+    TX_PER_BLOCK = 2
+
     # === Default ports ===
     RPC_PORT = 2332
     PEER_DEFAULT_PORTS = {'t': '2333', 's': '52333'}
@@ -45,6 +50,11 @@ class PalladiumTestnet(Palladium):
     # === Genesis hash (Bitcoin testnet) ===
     GENESIS_HASH = "000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943"
 
+    # === Network statistics (required by ElectrumX) ===
+    TX_COUNT = 500
+    TX_COUNT_HEIGHT = 1
+    TX_PER_BLOCK = 2
+
     # === Testnet ports ===
     RPC_PORT = 12332
     PEER_DEFAULT_PORTS = {'t': '12333', 's': '62333'}