fix(ci): start Radicale in its own step - GITHUB_ENV reaches only later steps (#156)

Files changed:
- .gitea/scripts/start-radicale.sh
- .gitea/workflows/ci.yml

.gitea/scripts/start-radicale.sh

@@ -23,7 +23,8 @@ htpasswd_encryption = plain
 [storage]
 filesystem_folder = $work/data
 CONF
-"$python" -m radicale --config "$work/config" > "$work/radicale.log" 2>&1 &
+# nohup: the server has to outlive this step's shell - the suite runs in the next step.
+nohup "$python" -m radicale --config "$work/config" > "$work/radicale.log" 2>&1 &
 # The readiness probe uses the same Python, not curl: ci.yml's job image has no curl.
 ready='
 import base64, sys, urllib.request