Improve image versioning and repo consistency

[shenkeyao]

Closes https://app.asana.com/1/1208976916964769/project/1209392461754458/task/1211735359000841?focus=true.

This PR:

• Adds a pre-commit hook to warn about any change on .env or docker-compose.
• Adds warnings to these two files.
• Moves the lighthouse and dev node images to a shared file.

Key places to review:

• The pre-commit hook scrip.

How to test this PR:

• Make a change to .env or docker-compose, commit it, and see if the git warning works.

[dailinsubjam]

Very helpful!