Fix: clear profession icons for non-item tooltips (pfUI-compatible)

[gitGrom]

Problem
After hovering an item reagent, the profession icons remain (“stick”) when the next
tooltip is a unit/spell (e.g., pet, NPC) until a non-crafting item is hovered.

Cause
Icons are only hidden on subsequent item tooltips; non-item tooltip code paths
reuse the same tooltip but don’t clear the icons.

Fix

• Clear icons before building non-item tooltips: SetUnit, SetSpell, SetTrainerService.
• Also clear on ClearLines() and OnHide().
• Hook both stock GameTooltip and pfUI tooltip frames when present.
• No behavior change for item tooltips; no saved data changes.

Tested
Vanilla/Turtle with pfUI tooltips:

1. Hover Copper Bar → icons appear.
2. Hover unit (bank mule/pet) → icons disappear immediately.
3. Hover item again → icons return.

Fixes #<1>.