babylon: add mainnet babylond pruned compose (bbn-1)

Family-C CometBFT node with statesync, wasm-only snapshot bootstrap,
and babylon-specific config (timeout_commit, btc-config, iavl-cache).

Co-authored-by: Cursor <cursoragent@cursor.com>

babylon/cometbft.Dockerfile

@@ -0,0 +1,11 @@
+ARG CL_IMAGE
+ARG CL_VERSION
+FROM ${CL_IMAGE}:${CL_VERSION}
+# Layer the shared CometBFT bootstrap lib + the chain init.sh onto the upstream
+# babylond binary image (alpine-based, has sh+apk; runs nonroot by default — the compose
+# sets user: root so init.sh can apk-add curl and write the /root home).
+USER root
+COPY ./scripts/cometbft-common.sh /usr/local/bin/cometbft-common.sh
+COPY ./scripts/init.sh            /usr/local/bin/init.sh
+RUN chmod +x /usr/local/bin/init.sh /usr/local/bin/cometbft-common.sh
+ENTRYPOINT ["init.sh"]