Here is a list of all documented namespaces with brief descriptions:

NBreakpointColumn	Column indices for the Breakpoints tree model
NLegacyColorPrefsMigration
NLuaDbgBreakpointModes	Inline editor mode metadata for the Breakpoints "Location" column
NLuaDebuggerMainClosePolicy	Pause-aware arbitration for main-window close while the Lua debugger is involved
Nmake	-taps
NPinnedOverlayView	Setup shared by PinnedColumnView and PinnedRowView, the two QTreeView-based overlay panes used to keep frozen columns/pinned rows visible alongside the primary packet list. Factored out so a fix to one overlay's base configuration (or its boundary-divider widget) can't be applied to only one of the two views by mistake
NStackColumn	Column indices for the Stack Trace tree model
Nubxdump
NVariablesColumn	Column indices for the Variables tree model
NWatchColumn	Column indices for the Watch tree model