Feat: Scripts for typical user workflows

[hopeyen]

Problem statement
When users come and they think...

1. I want to publish and serve a subgraph snapshot for the arbitrum-one network subgraph at the current block from my database. What do?
2. I want to publish firehose flatfiles for ethereum mainnet that contains block number from 17000000 to 19000000. What do?
3. I want to find and download flatfiles for a substream-enabled subgraph for its entire history. What do?

Expectation proposal

Provide scripts and clear documentation that helps making these use cases trivial to run