docs: Add recent development summaries to CONTEXT.md

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

CONTEXT.md

@@ -45,3 +45,15 @@ Development Summary:
     • The drawing logic was encapsulated into a dedicated `FeatureBrowser` class to improve modularity.
     • Position was set to the top-left corner and font size was increased for better visibility.
     • Fixed a linker error by adding the new `FeatureBrowser.cpp` source file to the `CMakeLists.txt` build configuration.
+12 View Cube Rendering Fix:
+    • Resolved a rendering glitch where the View Cube appeared transparent on startup by enabling the OpenGL depth test (`GL_DEPTH_TEST`) and face culling (`GL_CULL_FACE`) at the beginning of each frame's render cycle.
+13 Sketch Mode UI and State Management:
+    • Implemented a dedicated "SKETCH" UI mode. When a sketch is created, the main toolbar tabs are replaced with a single "SKETCH" tab.
+    • Added "Line", "Rectangle", "Circle", and "Save Sketch" tool buttons to the sketch tab, complete with new SVG icons.
+    • Fixed an issue where tool buttons only showed icons; they now display text labels below the icons for clarity.
+    • The sketch grid is now only rendered when in sketch mode.
+14 Camera Animation and View Presets:
+    • Implemented smooth camera transitions when entering and exiting sketch mode. The camera animates to a view normal to the sketch plane and animates back to its original position when the sketch is saved.
+    • This was achieved by converting camera parameters into Qt properties and using `QPropertyAnimation`.
+    • Resolved a C++ build error caused by naming conflicts between camera state member variables and their accessor methods.
+    • The default startup camera view was changed to a standard isometric angle for a better initial perspective.