Add prepare_incremental_render_path for incremental rendering

Extract common path generation logic into build_render_path and add
support for incremental rendering endpoint paths.

Changes:
- Add prepare_incremental_render_path method for generating
  /bundles/{hash}/incremental-render/{digest} paths
- Extract shared logic to private build_render_path method
- Supports both server and RSC bundle selection
- Add minimal tests covering path format and bundle selection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: AbanoubGhadban

react_on_rails_pro/lib/react_on_rails_pro/server_rendering_pool/node_rendering_pool.rb

@@ -96,16 +96,27 @@ def rsc_bundle_hash
         end
 
         def prepare_render_path(js_code, render_options)
+          # TODO: Remove the request_digest. See https://github.com/shakacode/react_on_rails_pro/issues/119
+          # From the request path
+          # path = "/bundles/#{@bundle_hash}/render"
+          build_render_path(js_code, render_options, "render")
+        end
+
+        def prepare_incremental_render_path(js_code, render_options)
+          build_render_path(js_code, render_options, "incremental-render")
+        end
+
+        private
+
+        def build_render_path(js_code, render_options, endpoint)
           ReactOnRailsPro::ServerRenderingPool::ProRendering
             .set_request_digest_on_render_options(js_code, render_options)
 
           rsc_support_enabled = ReactOnRailsPro.configuration.enable_rsc_support
           is_rendering_rsc_payload = rsc_support_enabled && render_options.rsc_payload_streaming?
           bundle_hash = is_rendering_rsc_payload ? rsc_bundle_hash : server_bundle_hash
-          # TODO: Remove the request_digest. See https://github.com/shakacode/react_on_rails_pro/issues/119
-          # From the request path
-          # path = "/bundles/#{@bundle_hash}/render"
-          "/bundles/#{bundle_hash}/render/#{render_options.request_digest}"
+
+          "/bundles/#{bundle_hash}/#{endpoint}/#{render_options.request_digest}"
         end
 
         def fallback_exec_js(js_code, render_options, error)

react_on_rails_pro/spec/react_on_rails_pro/server_rendering_pool/node_rendering_pool_spec.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+module ReactOnRailsPro
+  module ServerRenderingPool
+    RSpec.describe NodeRenderingPool do
+      let(:js_code) { "console.log('test');" }
+      let(:render_options) do
+        instance_double(
+          ReactOnRails::ReactComponent::RenderOptions,
+          request_digest: "abc123",
+          rsc_payload_streaming?: false
+        )
+      end
+
+      before do
+        allow(ReactOnRailsPro::ServerRenderingPool::ProRendering)
+          .to receive(:set_request_digest_on_render_options)
+        allow(ReactOnRailsPro.configuration).to receive(:enable_rsc_support).and_return(false)
+        allow(described_class).to receive(:server_bundle_hash).and_return("server123")
+        allow(described_class).to receive(:rsc_bundle_hash).and_return("rsc456")
+      end
+
+      describe ".prepare_incremental_render_path" do
+        it "returns path with incremental-render endpoint" do
+          path = described_class.prepare_incremental_render_path(js_code, render_options)
+
+          expect(path).to eq("/bundles/server123/incremental-render/abc123")
+        end
+
+        context "when RSC support is enabled and rendering RSC payload" do
+          before do
+            allow(ReactOnRailsPro.configuration).to receive(:enable_rsc_support).and_return(true)
+            allow(render_options).to receive(:rsc_payload_streaming?).and_return(true)
+          end
+
+          it "uses RSC bundle hash instead of server bundle hash" do
+            path = described_class.prepare_incremental_render_path(js_code, render_options)
+
+            expect(path).to eq("/bundles/rsc456/incremental-render/abc123")
+          end
+        end
+      end
+    end
+  end
+end