Mint campaign UTM links through the piha.li shortener.

Closes #9.

Auto-insert tracked homepage links in campaign compose, register them with
url_shortening_service, and put short piha.li URLs in SMS, email hrefs, and
postcard QR codes when SHORTENER_* is configured.

.env.prod.example

@@ -87,6 +87,13 @@ OLLAMA_BASE_URL=http://10.0.0.128:11434
 OLLAMA_MODEL=llama3.2
 OLLAMA_TIMEOUT_SECONDS=120
 
+# URL shortener — mint short links for campaign SMS / email / postcard QR.
+# POST /api/links/ on the API host. Recipients hit https://piha.li/<code>.
+# Token must match SHORTENER_API_TOKENS on url_shortening_service (name:secret).
+# Generate: python -c "import secrets; print(secrets.token_urlsafe(32))"
+SHORTENER_BASE_URL=https://shortener.aimloperations.com
+SHORTENER_API_TOKEN=monica:replace-me
+
 # Nominatim address suggest (server-side proxy only; not called from browser)
 NOMINATIM_BASE_URL=http://10.0.0.128:8089
 NOMINATIM_TIMEOUT_SECONDS=8
@@ -123,3 +130,5 @@ GUNICORN_BIND=0.0.0.0:8000
 # OLLAMA_BASE_URL=http://10.0.0.128:11434
 # NOMINATIM_BASE_URL=http://10.0.0.128:8089
 # NOMINATIM_COUNTRY_CODES=us
+# SHORTENER_BASE_URL=https://shortener-beta.aimloperations.com
+# SHORTENER_API_TOKEN=monica:replace-with-a-different-token