refactor: Add external LLMCore lib (#334)

* feat: Add LLMCore submodule

pluginllmcore/Provider.hpp

@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2024-2025 Petr Mironychev
+ *
+ * This file is part of QodeAssist.
+ *
+ * QodeAssist is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * QodeAssist is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with QodeAssist. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <QFlags>
+#include <QFuture>
+#include <QObject>
+#include <QString>
+#include <utils/environment.h>
+
+#include "ContextData.hpp"
+#include "IToolsManager.hpp"
+#include "PromptTemplate.hpp"
+#include "RequestType.hpp"
+
+namespace LLMCore {
+class BaseClient;
+class ToolsManager;
+}
+
+class QJsonObject;
+
+namespace QodeAssist::PluginLLMCore {
+
+enum class ProviderCapability {
+    Tools        = 0x1,
+    Thinking     = 0x2,
+    Image        = 0x4,
+    ModelListing = 0x8,
+};
+Q_DECLARE_FLAGS(ProviderCapabilities, ProviderCapability)
+Q_DECLARE_OPERATORS_FOR_FLAGS(ProviderCapabilities)
+
+class Provider : public QObject
+{
+    Q_OBJECT
+public:
+    explicit Provider(QObject *parent = nullptr);
+
+    virtual ~Provider() = default;
+
+    virtual QString name() const = 0;
+    virtual QString url() const = 0;
+    virtual QString completionEndpoint() const = 0;
+    virtual QString chatEndpoint() const = 0;
+    virtual void prepareRequest(
+        QJsonObject &request,
+        PluginLLMCore::PromptTemplate *prompt,
+        PluginLLMCore::ContextData context,
+        PluginLLMCore::RequestType type,
+        bool isToolsEnabled,
+        bool isThinkingEnabled)
+        = 0;
+    virtual QFuture<QList<QString>> getInstalledModels(const QString &url) = 0;
+    virtual ProviderID providerID() const = 0;
+    virtual ProviderCapabilities capabilities() const { return {}; }
+
+    virtual ::LLMCore::BaseClient *client() const = 0;
+    virtual QString apiKey() const = 0;
+
+    RequestID sendRequest(const QUrl &url, const QJsonObject &payload);
+    void cancelRequest(const RequestID &requestId);
+    ::LLMCore::ToolsManager *toolsManager() const;
+};
+
+} // namespace QodeAssist::PluginLLMCore