gui: Ctrl+F filter bar to search chat messages

Adds a filterText property to ChatBlockModel that filters all
parsed blocks by case-insensitive substring match on content
or tool/call name. Toggle the filter bar with Ctrl+F; Escape
or the close button clears the filter and hides the bar.
Shows match count while filtering.

gui/ChatPane.qml

@@ -165,6 +165,42 @@ Item {
 
         Rectangle { Layout.fillWidth: true; height: 1; color: palette.mid }
 
+        // Filter bar (Ctrl+F)
+        RowLayout {
+            id: filterBar
+            Layout.fillWidth: true
+            Layout.margins: 4
+            spacing: 4
+            visible: false
+
+            TextField {
+                id: filterInput
+                Layout.fillWidth: true
+                placeholderText: "Filter messages..."
+                onTextChanged: paneModel.filterText = text
+                Keys.onEscapePressed: {
+                    filterBar.visible = false
+                    paneModel.filterText = ""
+                    text = ""
+                }
+            }
+
+            Label {
+                text: paneModel.filtering ? paneModel.rowCount() + " matches" : ""
+                opacity: 0.6
+                font.pixelSize: Qt.application.font.pixelSize * 0.85
+            }
+
+            ToolButton {
+                icon.name: "window-close"
+                onClicked: {
+                    filterBar.visible = false
+                    paneModel.filterText = ""
+                    filterInput.text = ""
+                }
+            }
+        }
+
         // Chat view
         Item {
             Layout.fillWidth: true
@@ -529,6 +565,21 @@ Item {
 
 
 
+    // Filter shortcut
+    Shortcut {
+        sequence: "Ctrl+F"
+        onActivated: {
+            filterBar.visible = !filterBar.visible
+            if (filterBar.visible) {
+                filterInput.forceActiveFocus()
+                filterInput.selectAll()
+            } else {
+                paneModel.filterText = ""
+                filterInput.text = ""
+            }
+        }
+    }
+
     // Sloppy focus — focus prompt when mouse hovers inside pane
     HoverHandler {
         id: sloppyHover

gui/chatblockmodel.cpp

@@ -36,15 +36,17 @@ ChatBlockModel::ChatBlockModel(QObject *parent)
 int ChatBlockModel::rowCount(const QModelIndex &parent) const
 {
     if (parent.isValid()) return 0;
-    return m_blocks.size();
+    const auto &blocks = m_filterText.isEmpty() ? m_blocks : m_filteredBlocks;
+    return blocks.size();
 }
 
 QVariant ChatBlockModel::data(const QModelIndex &index, int role) const
 {
-    if (!index.isValid() || index.row() >= m_blocks.size())
+    const auto &blocks = m_filterText.isEmpty() ? m_blocks : m_filteredBlocks;
+    if (!index.isValid() || index.row() >= blocks.size())
         return {};
 
-    const ChatBlock &block = m_blocks[index.row()];
+    const ChatBlock &block = blocks[index.row()];
     switch (role) {
     case BlockTypeRole: {
         switch (block.type) {
@@ -108,9 +110,36 @@ void ChatBlockModel::setRawText(const QString &text)
     if (text == m_rawText) return;
     m_rawText = text;
     reparse();
+    if (!m_filterText.isEmpty())
+        applyFilter();
     emit rawTextChanged();
 }
 
+void ChatBlockModel::setFilterText(const QString &text)
+{
+    if (text == m_filterText) return;
+    m_filterText = text;
+    applyFilter();
+    emit filterTextChanged();
+}
+
+void ChatBlockModel::applyFilter()
+{
+    beginResetModel();
+    if (m_filterText.isEmpty()) {
+        m_filteredBlocks.clear();
+    } else {
+        m_filteredBlocks.clear();
+        for (const auto &block : m_allBlocks) {
+            if (block.content.contains(m_filterText, Qt::CaseInsensitive) ||
+                block.name.contains(m_filterText, Qt::CaseInsensitive)) {
+                m_filteredBlocks.append(block);
+            }
+        }
+    }
+    endResetModel();
+}
+
 static constexpr int INITIAL_BLOCKS = 20;
 static constexpr int LOAD_MORE_COUNT = 30;
 

gui/chatblockmodel.h

@@ -41,6 +41,8 @@ class ChatBlockModel : public QAbstractListModel
 {
     Q_OBJECT
     Q_PROPERTY(QString rawText READ rawText WRITE setRawText NOTIFY rawTextChanged)
+    Q_PROPERTY(QString filterText READ filterText WRITE setFilterText NOTIFY filterTextChanged)
+    Q_PROPERTY(bool filtering READ filtering NOTIFY filterTextChanged)
 
 public:
     enum Roles {
@@ -60,6 +62,10 @@ public:
     QString rawText() const { return m_rawText; }
     void setRawText(const QString &text);
 
+    QString filterText() const { return m_filterText; }
+    void setFilterText(const QString &text);
+    bool filtering() const { return !m_filterText.isEmpty(); }
+
     Q_INVOKABLE QString highlightedHtml(const QString &code, const QString &language) const;
     Q_INVOKABLE QString prettyJson(const QString &text) const;
     Q_INVOKABLE void copyToClipboard(const QString &text) const;
@@ -71,16 +77,20 @@ public:
 
 signals:
     void rawTextChanged();
+    void filterTextChanged();
 
 private:
     void reparse();
     void updateVisibleWindow();
+    void applyFilter();
     QList<ChatBlock> parseBlocks(const QString &text) const;
     QVariantList parseSubBlocks(const QString &content) const;
 
     QString m_rawText;
+    QString m_filterText;
     QList<ChatBlock> m_allBlocks;   // all parsed blocks
     QList<ChatBlock> m_blocks;      // visible window (tail of m_allBlocks)
+    QList<ChatBlock> m_filteredBlocks; // filtered subset when filterText is active
     int m_visibleStart = 0;         // index into m_allBlocks where visible window starts
     mutable QHash<QString, QString> m_highlightCache;
 };

gui/main-kf5.qml

@@ -770,6 +770,18 @@ ApplicationWindow {
         }
     }
 
+    Shortcut {
+        sequence: "Ctrl+F"
+        onActivated: {
+            var pane = mainContent.panes[mainContent.focusedPaneIndex]
+            if (!pane) return
+            var fb = pane.children[0] // ColumnLayout
+            // Toggle via the filterBar id inside the pane
+            // Since filterBar is inside the Component, access via pane property
+            pane.toggleFilter()
+        }
+    }
+
     // Handle pane swap: find target pane at drop coordinates
     function handlePaneSwap(sourcePane, rootX, rootY) {
         for (var i = 0; i < mainContent.panes.length; i++) {
@@ -845,6 +857,17 @@ ApplicationWindow {
                 if (sessionId !== "") refreshPaneChat()
             }
 
+            function toggleFilter() {
+                filterBar.visible = !filterBar.visible
+                if (filterBar.visible) {
+                    filterInput.forceActiveFocus()
+                    filterInput.selectAll()
+                } else {
+                    paneModel.filterText = ""
+                    filterInput.text = ""
+                }
+            }
+
             function refreshPaneChat() {
                 paneModel.rawText = ""
                 chatOffset = 0
@@ -973,6 +996,42 @@ ApplicationWindow {
 
                 Rectangle { Layout.fillWidth: true; height: 1; color: palette.mid }
 
+                // Filter bar (Ctrl+F)
+                RowLayout {
+                    id: filterBar
+                    Layout.fillWidth: true
+                    Layout.margins: 4
+                    spacing: 4
+                    visible: false
+
+                    TextField {
+                        id: filterInput
+                        Layout.fillWidth: true
+                        placeholderText: "Filter messages..."
+                        onTextChanged: paneRoot.paneModel.filterText = text
+                        Keys.onEscapePressed: {
+                            filterBar.visible = false
+                            paneRoot.paneModel.filterText = ""
+                            text = ""
+                        }
+                    }
+
+                    Label {
+                        text: paneRoot.paneModel.filtering ? paneRoot.paneModel.rowCount() + " matches" : ""
+                        opacity: 0.6
+                        font.pixelSize: Qt.application.font.pixelSize * 0.85
+                    }
+
+                    ToolButton {
+                        icon.name: "window-close"
+                        onClicked: {
+                            filterBar.visible = false
+                            paneRoot.paneModel.filterText = ""
+                            filterInput.text = ""
+                        }
+                    }
+                }
+
                 // Chat view
                 Item {
                     Layout.fillWidth: true