feat: Allow adding breakpoints in pattern editor by clicking on line numbers (#2161)

Now that line numbers are not part of the line of code clicking them
makes the text editor lose focus. This PR changes that by allowing the
user to toggle breakpoints by clicking the field where the line number
is located.

Not only will the text editor retain focus when breakpoints are set, but
if other parts of ImHex had focus, then it will be transferred to the
text editor's current cursor position when the line number field is
clicked.

It is also possible to keep the focus where it was and only retain the
focus if the text editor was focused when the break point is set. The
change is very trivial so if that is preferred I can easily switch it.

Author: paxcut

lib/third_party/imgui/ColorTextEditor/source/TextEditor.cpp

@@ -871,7 +871,7 @@ void TextEditor::SetFocus() {
     ResetCursorBlinkTime();
     EnsureCursorVisible();
     if (!this->mReadOnly) {
-        ImGui::SetKeyboardFocusHere(-1);
+        ImGui::SetKeyboardFocusHere(0);
         mUpdateFocus = false;
     }
 }
@@ -976,6 +976,15 @@ void TextEditor::RenderText(const char *aTitle, const ImVec2 &lineNumbersStartPo
                     space += " ";
                 }
                 std::string lineNoStr = space + std::to_string((int)(lineNo + 1));
+                ImGui::SetCursorScreenPos(ImVec2(lineNumbersStartPos.x, lineStartScreenPos.y));
+                if (ImGui::InvisibleButton(lineNoStr.c_str(),ImVec2(mLineNumberFieldWidth,mCharAdvance.y))) {
+                    if (mBreakpoints.contains(lineNo + 1))
+                        mBreakpoints.erase(lineNo + 1);
+                    else
+                        mBreakpoints.insert(lineNo + 1);
+                    mBreakPointsChanged = true;
+                    JumpToCoords(mState.mCursorPosition);
+                }
                 TextUnformattedColoredAt(ImVec2(mLeftMargin + lineNoStartScreenPos.x, lineStartScreenPos.y), mPalette[(int) PaletteIndex::LineNumber], lineNoStr.c_str());
             }