Refactor supervisor to use environment variables and simplify binary

- Created scripts/generate_secret.sh to generate supervisor secrets
- Added .env.example with all configuration options
- Created scripts/environment.sh to load env vars from .env
- Updated scripts/run.sh to use env vars and pass as flags
- Simplified supervisor binary:
  - Removed bootstrap-admin-key and config file support
  - Made admin-secret required
  - Minimal output (only URLs)
  - Clean startup with no verbose logging
- Updated .gitignore for .env and log files

scripts/generate_secret.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+# Generate a supervisor secret key in the correct format
+
+# Generate a random 32-byte hex string
+SECRET=$(openssl rand -hex 32)
+
+echo "Generated supervisor secret:"
+echo "$SECRET"
+echo ""
+echo "Add this to your .env file:"
+echo "SUPERVISOR_ADMIN_SECRET=$SECRET"