feat: add support code completion via acp

sources/context/CompletionContextEnricher.hpp

@@ -0,0 +1,42 @@
+// Copyright (C) 2026 Petr Mironychev
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Additional attribution terms under GPLv3 §7(b) apply — see LICENSE
+
+#pragma once
+
+#include <QString>
+#include <QStringList>
+
+#include "IDocumentReader.hpp"
+
+namespace QodeAssist::Context {
+
+class ICompletionEnricher
+{
+public:
+    virtual ~ICompletionEnricher() = default;
+
+    virtual QString enrichmentFor(
+        const DocumentInfo &documentInfo,
+        const QString &prefix,
+        int line,
+        int column,
+        int maxTokens)
+        = 0;
+};
+
+class SemanticContextEnricher : public ICompletionEnricher
+{
+public:
+    QString enrichmentFor(
+        const DocumentInfo &documentInfo,
+        const QString &prefix,
+        int line,
+        int column,
+        int maxTokens) override;
+};
+
+QString clampSectionsToTokenBudget(const QStringList &sections, int maxTokens);
+QStringList identifiersNearCursor(const QString &prefix, int maxIdentifiers);
+
+} // namespace QodeAssist::Context