fix(gowlers-tracking-ledger): link XP gains to encounters after combat ends

- Add lastCombatId and lastCombatEndTime tracking to preserve encounter data
- Update recordHistoryEntry to link XP within 5 seconds of combat end to last encounter
- Change encounter status from 'ended' to 'finished' for clarity
- Store encounter ID when combat ends to catch post-combat XP awards

Fixes issue where XP gained after combat ends was not linked to the encounter,
and encounters were not being marked as finished in the history.

Update version to 0.1.8

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

src/macros_new/gowlers-tracking-ledger/module.json

@@ -3,7 +3,7 @@
   "type": "module",
   "title": "Gowler's Tracking Ledger",
   "description": "Adds HP/XP/Currency log buttons to PF1 sheets and opens the tracking dialog preloaded with the actor's logs.",
-  "version": "0.1.7",
+  "version": "0.1.8",
   "authors": [
     { "name": "Gowler", "url": "https://foundryvtt.com" }
   ],