MidnightNameplates 0.10.2.3 - Import/Export Confirmation Pass

EXPORT
- Generate Export now opens a confirmation panel.
- Shows the selected export type.
- GENERATE confirms.
- CANCEL aborts.

IMPORT
- Import now requires Preview Import first, as before.
- Pressing IMPORT opens a confirmation panel.
- Confirmation shows:
  format/type/source summary
  selected import mode
  destructive warning for REPLACE
- IMPORT NOW applies.
- CANCEL aborts.

WARNINGS
- FULL / PROFILE + REPLACE:
  explicit warning that current profile configuration will be overwritten.
- RULE data + REPLACE:
  warns that current rule data will be replaced.
- MERGE:
  explains that imported data will be added to current data.

PROFILE DELETE
- Existing delete confirmation remains unchanged.

TEST
1. Generate FULL export -> confirmation appears.
2. Cancel -> no export generated.
3. Generate again -> confirm -> export string appears.
4. Preview a FULL import -> press IMPORT -> destructive warning appears.
5. Cancel -> settings unchanged.
6. Confirm -> import applies.
7. Test RULE_PACK + MERGE confirmation text.
8. Delete-profile confirmation still works.
9. No Lua errors.
