fix: Resolve compilation errors and build successfully

Build fixes:
- Add missing includes (<cstdint>, <iomanip>, <sstream>, <string>, <vector>)
- Fix unused parameter warnings with (void) casts
- Fix cpp-httplib API: Use UploadFormDataItems instead of MultipartFormDataItems
- Fix portaudio linking: Use portaudio_static target instead of portaudio

All modules now compile without errors. Executable built successfully (13MB).

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

Co-Authored-By: Claude <noreply@anthropic.com>

CMakeLists.txt

@@ -40,7 +40,7 @@ target_include_directories(${PROJECT_NAME} PRIVATE
 
 # Link libraries
 target_link_libraries(${PROJECT_NAME} PRIVATE
-    portaudio
+    portaudio_static
     httplib::httplib
     nlohmann_json::nlohmann_json
     imgui::imgui

src/api/WhisperClient.cpp

@@ -47,17 +47,16 @@ std::optional<WhisperResponse> WhisperClient::transcribe(
     httplib::Client client("https://api.openai.com");
     client.set_read_timeout(30, 0);  // 30 seconds timeout
 
-    httplib::MultipartFormDataItems items = {
-        {"file", wav_data, "audio.wav", "audio/wav"},
-        {"model", "whisper-1", "", ""},
-        {"language", language, "", ""},
-        {"temperature", std::to_string(temperature), "", ""}
-    };
-
     httplib::Headers headers = {
         {"Authorization", "Bearer " + api_key_}
     };
 
+    httplib::UploadFormDataItems items;
+    items.push_back({"file", wav_data, "audio.wav", "audio/wav"});
+    items.push_back({"model", "whisper-1", "", ""});
+    items.push_back({"language", language, "", ""});
+    items.push_back({"temperature", std::to_string(temperature), "", ""});
+
     auto res = client.Post("/v1/audio/transcriptions", headers, items);
 
     if (!res) {

src/audio/AudioBuffer.cpp

@@ -1,6 +1,7 @@
 #include "AudioBuffer.h"
 #include <fstream>
 #include <cstring>
+#include <cstdint>
 #include <algorithm>
 
 namespace secondvoice {

src/audio/AudioCapture.cpp

@@ -31,6 +31,10 @@ int AudioCapture::audioCallback(const void* input, void* output,
                                 const PaStreamCallbackTimeInfo* time_info,
                                 PaStreamCallbackFlags status_flags,
                                 void* user_data) {
+    (void)output;       // Unused
+    (void)time_info;    // Unused
+    (void)status_flags; // Unused
+
     AudioCapture* self = static_cast<AudioCapture*>(user_data);
     const float* in = static_cast<const float*>(input);
 

src/core/Pipeline.cpp

@@ -6,6 +6,8 @@
 #include "../ui/TranslationUI.h"
 #include "../utils/Config.h"
 #include <iostream>
+#include <iomanip>
+#include <sstream>
 #include <chrono>
 #include <filesystem>
 

src/core/Pipeline.h

@@ -3,6 +3,8 @@
 #include <memory>
 #include <thread>
 #include <atomic>
+#include <string>
+#include <vector>
 #include "../utils/ThreadSafeQueue.h"
 
 namespace secondvoice {

src/main.cpp

@@ -3,6 +3,8 @@
 #include "core/Pipeline.h"
 
 int main(int argc, char** argv) {
+    (void)argc; // Unused
+    (void)argv; // Unused
     std::cout << "SecondVoice - Real-time Translation System" << std::endl;
     std::cout << "===========================================" << std::endl;