The get_screenshot tool inherited the MFC thumbnail-preview profile, capping
the frame at 1024px wide (1280 on 4K source), which is too small for AI
vision/OCR of dense UI. Add an optional max_width argument that overrides the
width (clamped to the client's 64..1920 limit) while keeping the RTT-adaptive
jpegQuality. Omitted or 0 keeps the existing thumbnail profile; 1920 yields
near-native resolution (full 1080p on a 1080p source, 1920 wide on 4K). Sync
the design doc.
Co-Authored-By: deepseek-v4-pro