feat: media_async + media_index modules, media_files table, tests

- media_async: thread-per-task async engine with primitives (sha256, sign, copy, uuid, file_size)
- media_index: media_files DB table with register_async for indexing chunks
- chat_msg: async media submission via register_async, simplified chat_msg_submit fields
- voice_recorder/attachment_sender: write single file (no chunk splitting on caller side)
- inputbar/messagelist: updated to new simplified submit interface
- test_media_async: 4-thread stress test (200K ops / 2 sec, 0 errors)
- test_media_index: 9 cases covering commit edge cases + async flow
- build: Makefile.am, CMakeLists.txt, utun_sources.cmake updated

tools/chatgui/src/storagesettingspage.cpp

@@ -0,0 +1,90 @@
+#include "storagesettingspage.h"
+#include "../db/db_manager.h"
+#include "../transport/gui_bridge.h"
+#include "../../lib/mem.h"
+extern "C" {
+#include "chat/chat_core.h"
+}
+#include <QVBoxLayout>
+#include <QFormLayout>
+#include <QCheckBox>
+#include <QSpinBox>
+#include <QLabel>
+#include <QFrame>
+
+static void saveUiStateInt(const char* key, int val) {
+    QByteArray v = QByteArray::number(val);
+    size_t klen = strlen(key), vlen = (size_t)v.size(), total = klen + 1 + vlen + 1;
+    if (total > 256) return;
+    void* arg = u_malloc(total);
+    memcpy(arg, key, klen + 1);
+    memcpy((char*)arg + klen + 1, v.constData(), vlen + 1);
+    gui_bridge_post_uasync_fn(chat_core_save_ui_state_trampoline, arg);
+}
+
+StorageSettingsPage::StorageSettingsPage(DbManager* db, QWidget* parent)
+    : QWidget(parent)
+    , m_db(db)
+{
+    auto* layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 12, 0, 0);
+    layout->setSpacing(14);
+
+    auto* title = new QLabel("Media Storage", this);
+    title->setStyleSheet("font-weight: bold; font-size: 13px;");
+    layout->addWidget(title);
+
+    auto* form = new QFormLayout();
+    form->setSpacing(10);
+    form->setContentsMargins(0, 8, 0, 0);
+
+    m_autoloadCheck = new QCheckBox("Autoload media", this);
+    m_autoloadCheck->setStyleSheet("font-size: 13px;");
+    form->addRow(m_autoloadCheck);
+
+    m_autoloadMaxSize = new QSpinBox(this);
+    m_autoloadMaxSize->setRange(1, 500);
+    m_autoloadMaxSize->setSuffix(" MB");
+    m_autoloadMaxSize->setFixedWidth(110);
+    m_autoloadMaxSize->setStyleSheet(
+        "QSpinBox { border: 1px solid palette(mid); border-radius: 4px;"
+        " padding: 5px 8px; font-size: 13px; background: palette(base); }");
+    form->addRow("Autoload max size:", m_autoloadMaxSize);
+
+    m_maxStorageSize = new QSpinBox(this);
+    m_maxStorageSize->setRange(1, 100);
+    m_maxStorageSize->setSuffix(" GB");
+    m_maxStorageSize->setFixedWidth(110);
+    m_maxStorageSize->setStyleSheet(
+        "QSpinBox { border: 1px solid palette(mid); border-radius: 4px;"
+        " padding: 5px 8px; font-size: 13px; background: palette(base); }");
+    form->addRow("Max storage size:", m_maxStorageSize);
+
+    layout->addLayout(form);
+
+    auto* sep = new QFrame(this);
+    sep->setFrameShape(QFrame::HLine);
+    sep->setStyleSheet("QFrame { color: palette(mid); }");
+    layout->addWidget(sep);
+
+    layout->addStretch();
+}
+
+void StorageSettingsPage::loadFromDb() {
+    if (!m_db) return;
+
+    bool autoload = m_db->getUiStateInt("storage_autoload", 1);
+    m_autoloadCheck->setChecked(autoload);
+
+    int maxSizeMb = m_db->getUiStateInt("storage_autoload_maxsize_mb", 10);
+    m_autoloadMaxSize->setValue(maxSizeMb);
+
+    int maxGb = m_db->getUiStateInt("storage_maxsize_gb", 1);
+    m_maxStorageSize->setValue(maxGb);
+}
+
+void StorageSettingsPage::applyAndSave() {
+    saveUiStateInt("storage_autoload", m_autoloadCheck->isChecked() ? 1 : 0);
+    saveUiStateInt("storage_autoload_maxsize_mb", m_autoloadMaxSize->value());
+    saveUiStateInt("storage_maxsize_gb", m_maxStorageSize->value());
+}