tools: add env preflight checker

[AndersonUece]

Added a quick env checker so users fail fast instead of debugging auth errors later.

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Note

Low Risk
Low risk: adds a standalone helper script that only reads .env/process environment and prints status, without touching runtime logic or data flows.

Overview
Adds scripts/check_env.py, a lightweight preflight checker that optionally loads key/value pairs from .env and validates required env vars (HOST, CHAIN_ID, PRIVATE_KEY, FUNDER). If any are missing it exits non-zero and prints the missing keys; otherwise it reports success.

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Cursor Bugbot has reviewed your changes and found 2 potential issues.

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Unused sys import

Low Severity

The sys module is imported but never used. The script uses raise SystemExit(main()) which doesn't require sys. This import can be removed.

 

[cursor]

Checker validates wrong environment variable names

High Severity

The REQUIRED list checks for HOST, CHAIN_ID, PRIVATE_KEY, FUNDER, but the actual example files in this codebase use different env var names: CLOB_API_URL, PK, CLOB_API_KEY, CLOB_SECRET, CLOB_PASS_PHRASE. No code in the repository actually reads the variables being checked, so this preflight checker won't catch the missing variables that cause auth errors.