Add custom packet detail columns

[NghiaTranUIT]

• Added Create Column to the packet detail right-click menu.
• Added a tooltip and a separator above it.
• Added custom packet table columns.
• Stop duplicate custom columns.
• Show or hide custom columns from the table header menu.
• Save column order, width, and hidden state.
• Reset columns removes custom columns and restores defaults.
• Added tests for the service and menu behavior.
• Build and tests pass.

[NghiaTranUIT]

Done ✅