docs(meta): improve player test instructions in test protocol

Make gameplay testing instructions more explicit — Claude Code
cannot launch CK3 or interact with the UI, so the test script
must clearly describe what the human player needs to do. Add
guidance on game speed and what to look for.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/TESTING.md

@@ -318,14 +318,16 @@ grep 'lords.of.ash' "$CK3_LOGS/setup.log"
 
 #### 4. Execute testing checkpoints
 
-Follow the testing checkpoints in the milestone doc. Use debug decisions to
-force conditions that are hard to trigger naturally.
+Follow the **Player Test Script** in the milestone doc (section below). Each
+milestone has a numbered list of specific in-game actions the player must
+perform. Claude Code cannot launch CK3 or interact with the UI — these steps
+require a human.
 
 For each checkpoint:
-1. Use the debug decision to set up the required state
-2. Verify the expected outcome
-3. Check `error.log` for new errors after each test
-4. Note any issues in a test report
+1. Perform the specific action described in the test script
+2. Verify the expected visual/gameplay outcome
+3. Note any issues (wrong text, missing icons, broken behavior)
+4. After all actions, quit to desktop so Claude Code can analyze logs
 
 #### 5. Extended playthrough
 
@@ -336,9 +338,11 @@ After all checkpoints pass:
 : > "$CK3_LOGS/error.log"
 ```
 
-- Play 20 in-game years (or as specified in the milestone doc)
+- Play the number of years specified in the milestone doc (default: 5 years)
+- Set game speed to 4 or 5
 - Observe for: vanilla bleed-through, event spam, broken mechanics,
   performance degradation
+- Note anything that looks wrong, even if it doesn't crash
 
 ```bash
 # After the playthrough, full log analysis: