chore: sync sproutclaw to gitea

- Remove unused .pi extensions and prompts
- Update generated model files
- Add context.md
- Update pi-test.sh and package-lock.json

pi-test.sh

@@ -6,7 +6,6 @@ SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 # Default to the repository-local pi config so this source checkout uses the
 # copied learning config instead of ~/.pi.
 export PI_CODING_AGENT_DIR="${PI_CODING_AGENT_DIR:-$SCRIPT_DIR/.pi/agent}"
-export PI_CODING_AGENT_SESSION_DIR="${PI_CODING_AGENT_SESSION_DIR:-$SCRIPT_DIR/.pi/sessions}"
 
 # Check for --no-env flag
 NO_ENV=false