14: Implement JSON-RPC call

src/main/tjava/com/r35157/libs/solana/impl/ref/SolanaBlockChainImpl.tjava

@@ -392,6 +392,52 @@ public class SolanaBlockChainImpl implements SolanaBlockChain {
         return Set.copyOf(accountInfos);
     }
 
+    private String createGetProgramAccountsBody(
+            ΩSolanaProgramIdΩ programId,
+            Set<SolanaProgramAccountMemcmpFilter> filters
+    ) throws IOException {
+        StringBuilder filtersJson = new StringBuilder();
+
+        boolean first = true;
+        for (SolanaProgramAccountMemcmpFilter filter : filters) {
+            if (!first) {
+                filtersJson.append(",");
+            }
+
+            filtersJson.append("""
+                {
+                    "memcmp": {
+                        "offset": %d,
+                        "bytes": "%s"
+                    }
+                }
+                """.formatted(
+                    filter.offset(),
+                    filter.bytes()
+            ));
+
+            first = false;
+        }
+
+        return """
+            {
+                "jsonrpc": "2.0",
+                "id": 1,
+                "method": "getProgramAccounts",
+                "params": [
+                    "%s",
+                    {
+                        "commitment": "finalized",
+                        "encoding": "base64",
+                        "filters": [
+                            %s
+                        ]
+                    }
+                ]
+            }
+            """.formatted(programId, filtersJson);
+    }
+
     private synchronized HttpResponse<String> sendThrottled(HttpRequest request) throws IOException, InterruptedException {
         waitBeforeRemoteCall();