fix: correct Dialyzer type specs in runtime modules

Update type specifications to match actual implementation behavior:

- Runtime.start/1: Returns port() directly, not {:ok, pid()}
- Runtime.terminate/2: Returns :normal | :shutdown | {:shutdown, term()}
  via cleanup_runtime_process/2 and normalize_exit_reason/1
- render_response: Simplified from GenServer reply tuple to direct result,
  as the __using__ macro wraps the response in {:reply, _, state}

Resolves all Dialyzer warnings in:
- lib/phoenix/react_server/runtime.ex
- lib/phoenix/react_server/runtime/bun.ex
- lib/phoenix/react_server/runtime/deno.ex

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

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

Author: GSMLG-BOT

lib/phoenix/react_server/runtime.ex

@@ -104,12 +104,14 @@ defmodule Phoenix.ReactServer.Runtime do
   @type runtime_config :: keyword()
 
   @typedoc "Render response"
-  @type render_response :: {:reply, {:ok, html()}, t()} | {:reply, {:error, term()}, t()}
+  @type render_response :: {:ok, html()} | {:error, term()}
 
   @doc """
   Starts the runtime with given arguments.
+
+  Returns a port that can be used to communicate with the runtime process.
   """
-  @callback start(start_args()) :: {:ok, pid()} | {:error, term()}
+  @callback start(start_args()) :: port()
 
   @doc """
   Starts a file watcher for the component directory.

lib/phoenix/react_server/runtime/bun.ex

@@ -142,7 +142,7 @@ defmodule Phoenix.ReactServer.Runtime.Bun do
   end
 
   @impl true
-  @spec start(Phoenix.ReactServer.Runtime.start_args()) :: port() | {:error, term()}
+  @spec start(Phoenix.ReactServer.Runtime.start_args()) :: port()
   def start(component_base: _component_base) do
     config = config()
     cmd = config[:cmd]
@@ -258,7 +258,8 @@ defmodule Phoenix.ReactServer.Runtime.Bun do
   end
 
   @impl true
-  @spec terminate(term(), Phoenix.ReactServer.Runtime.t()) :: :ok
+  @spec terminate(term(), Phoenix.ReactServer.Runtime.t()) ::
+          :normal | :shutdown | {:shutdown, term()}
   def terminate(reason, state) do
     Logger.debug("Bun.Server terminating")
     cleanup_runtime_process(state.runtime_port, reason)

lib/phoenix/react_server/runtime/deno.ex

@@ -156,6 +156,7 @@ defmodule Phoenix.ReactServer.Runtime.Deno do
   end
 
   @impl true
+  @spec start(Phoenix.ReactServer.Runtime.start_args()) :: port()
   def start(component_base: _component_base) do
     config = config()
     cmd = config[:cmd]
@@ -293,6 +294,8 @@ defmodule Phoenix.ReactServer.Runtime.Deno do
   end
 
   @impl true
+  @spec terminate(term(), Phoenix.ReactServer.Runtime.t()) ::
+          :normal | :shutdown | {:shutdown, term()}
   def terminate(reason, state) do
     Logger.debug("Deno.Server terminating")
     Telemetry.record_runtime_shutdown("Deno", reason)