feat: sync delegations

[gusin13]

This PR

1. Syncs delegation events when poller is running. Basically intercepts delegation data from tx events, then converts into concrete proto and inserts in the db
2. Fixes some minor things in local setup (connection string, args etc). Smh on my local 27017 for mongo doesn't work so I changed to 27019

Note:
Some helper functions (validation related) are placeholders and need improvement, will be done in future prs.
I had to add cosmos sdk as dependency b/c we need this function which converts event -> concrete proto types

[jrwbabylonlab]

Amazing work @gusin13