feat: add streamer-owned recording control service

Introduce a dedicated streamer-side recording control plane instead of sharing the producer recorder API.

- register streamer-owned recorder endpoints as a NATS micro service
- add explicit MP4 and MCAP recorder control protobufs and subject helpers
- wire recorder lifecycle handling into the pipeline runtime
- add MP4 writer and depth-alignment support files used by the new recording flow

include/cvmmap_streamer/record/mp4_record_writer.hpp

@@ -0,0 +1,70 @@
+#pragma once
+
+#include "cvmmap_streamer/config/runtime_config.hpp"
+
+#include <cstddef>
+#include <cstdint>
+#include <expected>
+#include <filesystem>
+#include <memory>
+#include <string_view>
+
+namespace cvmmap_streamer::record {
+
+inline constexpr int kDefaultMp4Quality = 23;
+
+enum class Mp4InputPixelFormat : std::uint8_t {
+	Bgr24,
+	Rgb24,
+	Bgra32,
+	Rgba32,
+	Gray8,
+};
+
+struct Mp4EncodeTuning {
+	int quality{kDefaultMp4Quality};
+	std::uint32_t gop{30};
+	std::uint32_t b_frames{0};
+};
+
+[[nodiscard]]
+std::string_view input_pixel_format_name(Mp4InputPixelFormat pixel_format);
+
+class Mp4RecordWriter {
+public:
+	Mp4RecordWriter();
+	Mp4RecordWriter(const Mp4RecordWriter &) = delete;
+	Mp4RecordWriter &operator=(const Mp4RecordWriter &) = delete;
+	Mp4RecordWriter(Mp4RecordWriter &&) noexcept;
+	Mp4RecordWriter &operator=(Mp4RecordWriter &&) noexcept;
+	~Mp4RecordWriter();
+
+	[[nodiscard]]
+	std::expected<void, std::string> open(
+		const std::filesystem::path &output_path,
+		CodecType codec,
+		EncoderDeviceType encoder_device,
+		std::uint32_t width,
+		std::uint32_t height,
+		float fps,
+		const Mp4EncodeTuning &tuning,
+		Mp4InputPixelFormat input_pixel_format);
+
+	[[nodiscard]]
+	std::expected<void, std::string> write_frame(
+		const std::uint8_t *data,
+		std::size_t row_stride_bytes,
+		std::uint64_t relative_timestamp_ns);
+
+	[[nodiscard]]
+	std::expected<void, std::string> flush();
+
+	[[nodiscard]]
+	bool using_hardware() const;
+
+private:
+	struct Impl;
+	std::unique_ptr<Impl> impl_{};
+};
+
+}  // namespace cvmmap_streamer::record