Method handle

src/fl/remote/rpc/rpc.cpp.hpp:67–186

// =============================================================================

json Rpc::handle(const json& request) {
    // Extract method name
    if (!request.contains("method")) {
        FL_ERROR("RPC: Invalid Request - missing 'method' field");
        return detail::makeJsonRpcError(-32600, "Invalid Request: missing 'method'", request["id"]);
    }

    auto methodOpt = request["method"].as_string();
    if (!methodOpt.has_value()) {
        FL_ERROR("RPC: Invalid Request - 'method' must be a string");
        return detail::makeJsonRpcError(-32600, "Invalid Request: 'method' must be a string", request["id"]);
    }
    fl::string methodName = methodOpt.value();

#if FL_PLATFORM_HAS_LARGE_MEMORY
    // Handle built-in rpc.discover method. Gated on Low-memory targets because
    // it transitively anchors `TypedSchemaGenerator<Sig>::params()` for every
    // registered method (each 800+ B per signature) plus the schema-building
    // JSON tree. The LPC8xx / AVR-class JSON-RPC bring-up surface treats the
    // RPC catalog as a known constant -- callers don't introspect at runtime.
    // See FastLED #3081.
    if (methodName == "rpc.discover") {
        json response = json::object();
        response.set("jsonrpc", "2.0");
        response.set("result", schema());
        if (request.contains("id")) {
            response.set("id", request["id"]);
        }
        return response;
    }
#endif

    // Look up the method
    auto it = mRegistry.find(methodName);
    if (it == mRegistry.end()) {
        FL_WARN("RPC: Method not found: " << methodName.c_str());
        return detail::makeJsonRpcError(-32601, "Method not found: " + methodName, request["id"]);
    }

    // Extract params (default to empty array)
    json params = request.contains("params") ? request["params"] : json::parse("[]");
    if (!params.is_array()) {
        FL_ERROR("RPC: Invalid params - must be an array for method: " << methodName.c_str());
        return detail::makeJsonRpcError(-32602, "Invalid params: must be an array", request["id"]);
    }

    // Check if this is an async function
    const detail::RpcEntry& entry = it->second;
    bool isAsync = (entry.mMode == RpcMode::ASYNC || entry.mMode == RpcMode::ASYNC_STREAM);

    // Check if this is a response-aware function (uses ResponseSend&)
    bool isResponseAware = entry.mIsResponseAware;

    // For async functions, send ACK immediately
    if (isAsync && mResponseSink && request.contains("id")) {
        json ack = json::object();
        ack.set("jsonrpc", "2.0");
        ack.set("id", request["id"]);