Update PC1 playtest instructions for the new dashboard controls

Replaces the manual multi-step shell commands (docker compose, alembic,
uvicorn with env vars, manual teardown) with the one-click dashboard
flow at /checkpoint/PC1 in ~/agp (commit 261c45f): Start Backend / Stop
& Clean Up, and Build / Download a pre-configured Windows .exe. No
terminal commands needed on either machine.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/checkpoints/PC1.md

@@ -37,45 +37,33 @@ the real scope of PC1; don't expect more when playtesting.
 
 ## Manual playtest: backend on cloudbison, client on pinkbison
 
-Cloudbison's LAN IP: `192.168.58.138`. Pinkbison's: `192.168.58.124`.
+As of 2026-08-20 this is dashboard-controlled — no terminal commands, no
+env vars, no editing files. Foolproof enough to hand to someone else.
 
-### 1. On cloudbison — start a real (persistent, not throwaway) backend
+### 1. On cloudbison — the AGP dashboard
 
-```bash
-cd ~
-git clone http://localhost:3000/daddy/agp-game.git agp-game-playtest
-cd agp-game-playtest/backend
-docker compose up -d postgres
-docker compose exec -T postgres pg_isready -U agp_user -d agp_db   # wait for this to succeed
+Open the dashboard (`http://cloudbison:7070`, or its Tailscale address) and
+go to **PC1** in the nav bar (`/checkpoint/PC1`). Click **Start Backend** —
+it pulls the latest `main`, stands up Postgres, runs migrations, and starts
+the API server, all in one step. The page shows the LAN address it's
+reachable at once it's up (under a minute).
 
-export DATABASE_URL="postgresql+asyncpg://agp_user:agp_password@localhost:5432/agp_db"
-export JWT_ALGORITHM="RS256"
-/home/daddy/agp/venv/bin/python3 -m alembic upgrade head
-nohup /home/daddy/agp/venv/bin/python3 -m uvicorn app.main:app --host 0.0.0.0 --port 8000 > /tmp/agp-backend.log 2>&1 &
-disown
-```
+When you're done playtesting, click **Stop & Clean Up** on the same page —
+it tears down everything that step started (API server, Postgres
+container, its volume and network). Nothing is left running or lying
+around afterward, even if the dashboard itself gets restarted in between.
 
-`--host 0.0.0.0` matters — the default `127.0.0.1` only listens on loopback
-and pinkbison won't be able to reach it. Verify: `curl
-http://localhost:8000/api/health` should return `{"status":"ok",...}`.
+### 2. On pinkbison — download and run the .exe
 
-### 2. On pinkbison — get the game and point it at cloudbison
-
-Copy `export/windows/agp-game.exe` (or `export/linux/agp-game.x86_64`,
-whichever matches pinkbison's OS) from cloudbison, or clone the repo there
-and run `scripts/build.sh` locally. Launch with the backend URL as an env
-var so you don't have to rebuild to change it:
-
-- Windows (PowerShell): `$env:AGP_API_BASE_URL="http://192.168.58.138:8000"; .\agp-game.exe`
-- Linux: `AGP_API_BASE_URL=http://192.168.58.138:8000 ./agp-game.x86_64`
+Same dashboard page: click **Build .exe** the first time (or **Rebuild** to
+pick up newer changes) — this pulls the latest `main` and exports a Windows
+binary with cloudbison's backend address already baked in. Click
+**Download agp-game.exe**, copy it to pinkbison, and just run it. No
+environment variable, no config file, no build step on pinkbison at all.
 
 ### 3. Tear down when done
 
-```bash
-# on cloudbison
-pkill -f "uvicorn app.main:app"
-cd ~/agp-game-playtest/backend && docker compose down -v
-```
+**Stop & Clean Up** on the dashboard page. That's it.
 
 ## Status