ipabusedb-docker-reporter: rename from ipabusedb-docker-ssh, add Dockerfile with runit service

Build on git.eeqj.de/sneak/baseimage:2026-11-05 with the docker CLI
copied from docker:cli. A runit service sleeps INTERVAL seconds
(default 1200), then runs the reporter with --since INTERVAL --submit;
DOCKER_CONTAINER_NAME and IPABUSEDB_API_KEY come from the container
environment. Add .dockerignore, make image, and README section; fix the
binary name in .gitignore.

ipabusedb-docker-reporter/go.sum

@@ -0,0 +1,2 @@
+github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
+github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=