[teloverge]

The viewer's traffic meter was fixed in the lower-right corner and could obscure remote desktop content. Allow users to drag the meter with the left mouse button to reposition it, keep it within the visible window, and consume the gesture locally so it sends no mouse-button events to the remote desktop.

Document the gesture in the -ShowStats manual entry.

Validation:

• cmake --build build --target vncviewer -j 4 passed.
• Native viewer checks passed for dragging, boundary clamping, window resizing, suppression of remote mouse-button events during dragging, and normal remote clicks afterward.
• git diff --check --cached passed.
• CTest found no tests configured in this build.