MidnightNameplates 0.9.4 - Phase 9.4 Advanced Matching

NEW NPC RULE CONDITIONS
- Require current target
- Require focus
- Classification: ANY / NORMAL / ELITE / RARE / RAREELITE / BOSS
- Unit type: ANY / ENEMY_NPC / FRIENDLY_NPC / ENEMY_PLAYER / FRIENDLY_PLAYER

NEW SPELL RULE CONDITIONS
- Require current target
- Require focus
- Interruptible: ANY / YES / NO
- Classification: ANY / NORMAL / ELITE / RARE / RAREELITE / BOSS
- Existing spell exact-name matching remains the primary key

MATCHING BEHAVIOR
- Multiple matching rules are resolved by priority:
  CRITICAL > HIGH > NORMAL > LOW
- Secret/restricted values are never coerced or compared.
- If a required condition cannot be safely evaluated, the rule does not match.

TEST
1. Existing rules still work with all conditions left at ANY/OFF.
2. NPC rule + Target condition.
3. NPC rule + Focus condition.
4. Elite/Boss classification condition.
5. Spell rule with Interruptible YES/NO.
6. Two matching rules with different priorities: higher priority must win.
7. Rules page scrollbar remains usable.
8. No Lua errors, taint or secret-value errors.
