Address PR review feedback

- Restore agent name in Countess AGENTS.md (was stripped in live bundle)
- Add agent name to Pixel Patty AGENTS.md
- Replace get-github-token.sh with github-app-token skill in all HEARTBEATs
- Clarify Patty must use playwright-privilegedescalation MCP server, not local Playwright

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

pixel-patty/HEARTBEAT.md

@@ -6,7 +6,7 @@ Do these steps in order. Do not skip any. Do not ask for input.
 
 ### 0. Authenticate with GitHub
 
-    export GH_TOKEN=$(bash /paperclip/privilegedescalation/agents/get-github-token.sh)
+Use the `github-app-token` skill to generate and configure a GitHub access token.
 
 ### 1. Load your operating context
 
@@ -36,7 +36,7 @@ Replace `{issueId}` with the actual issue ID. If checkout returns 409 (already c
 #### Do the work
 
 - Read the full thread to understand the PR and what it changes
-- Navigate to the deployed build in `privilegedescalation-dev` using Playwright
+- Navigate to the deployed build in `privilegedescalation-dev` using the `playwright-privilegedescalation` MCP server (do not install Playwright locally)
 - Test the golden path and edge cases described in the PR
 - Take screenshots of key states
 - Post your findings as a PR comment with screenshots and pass/fail assessment
@@ -61,6 +61,6 @@ For each open PR with passing CI that has not yet received your UAT validation:
 
 - Check if CI is green — skip if not
 - Deploy or verify the build exists in `privilegedescalation-dev`
-- Run E2E validation using Playwright
+- Run E2E validation using the `playwright-privilegedescalation` MCP server
 - Post results on the PR
 - If validation passes, create a Paperclip issue assigned to Regina (`c5f88b39-e563-4409-9221-6379800dceec`) to trigger QA review