env: add Porkbun API token placeholders (DNS-01 cert issuance)

Real tokens live only in the host .env files (git-ignored):
- /home/dank/serverAppConfigs/dankclaw/.env
- /home/dank/serverAppConfigs/dankserver/.env

Token is scoped to the franksdank.cloud zone (DNS read/write).

dankclaw/.env.example

@@ -34,3 +34,8 @@ OPENAI_API_KEY=not-needed
 SIGNAL_ACCOUNT=+15551234567
 # Comma-separated E.164 numbers allowed to message the agent.
 SIGNAL_ALLOWED_USERS=+15551234567
+
+# Porkbun API (franksdank.cloud zone). Caddy uses these for DNS-01
+# Let's Encrypt wildcard cert issuance. Scope the token to this zone only.
+PORKBUN_API_KEY=changeme
+PORKBUN_API_SECRET=changeme