[DOCS] Add safe .env.example and local setup guide for contributors

[Obiajulu-gif]

Overview

Create a safe contributor-friendly .env.example file and improve the local setup instructions so external contributors can run ChainMove without receiving maintainer API keys.

Problem

The project depends on services like MongoDB, Privy, Paystack, Resend, and planned Stellar infrastructure. Contributors need clear placeholder variables and mock-mode instructions so they do not ask for or accidentally expose private credentials.

Expected solution

• Add .env.example with safe placeholder values only.
• Document how to copy it to .env.local.
• Explain which variables are required, optional, or mock-only.
• Confirm .env* remains ignored by Git.
• Add mock-mode flags for payments, email, and Stellar.

Suggested variables

NEXT_PUBLIC_APP_URL=http://localhost:3000
MONGODB_URI=mongodb://localhost:27017/chainmove
JWT_SECRET=replace_with_local_dev_secret
NEXT_PUBLIC_PRIVY_APP_ID=replace_with_privy_app_id
PRIVY_APP_SECRET=replace_with_privy_secret
PRIVY_JWKS_URL=replace_with_privy_jwks_url
PAYSTACK_SECRET_KEY=replace_with_paystack_test_secret
PAYSTACK_DVA_PREFERRED_BANK=test-bank
RESEND_API_KEY=replace_with_resend_key
STELLAR_NETWORK=testnet
STELLAR_HORIZON_URL=https://horizon-testnet.stellar.org
STELLAR_RPC_URL=https://soroban-testnet.stellar.org
STELLAR_ASSET_CODE=CMOVE
STELLAR_ISSUER_PUBLIC_KEY=replace_with_public_key
STELLAR_DISTRIBUTION_PUBLIC_KEY=replace_with_public_key
STELLAR_CONTRACT_ID=replace_after_deployment
ENABLE_MOCK_PAYMENTS=true
ENABLE_MOCK_EMAILS=true
ENABLE_MOCK_STELLAR=true

Files likely involved

• .env.example
• README.md
• CONTRIBUTING.md

Acceptance criteria

• No real secret or private key is committed.
• .env.example contains only placeholders.
• README explains local setup clearly.
• Contributors can understand how to run the app without maintainer keys.

Suggested labels

documentation, good first issue, security, developer-experience

Difficulty

Good first issue

[Menjay7]

Hi! I came across this issue and would love to work on it. I have experience with similar tasks and I'm confident I can investigate, implement a clean solution, and thoroughly test it before submitting a PR. If the issue is still open, I would appreciate it if you could assign it to me. Thank you!

[githoboman]

hello would love to work on this project

[jaynomyaro]

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

[Ekenesamuel8]

hello sir, can i take this task

[OkeyAmy]

Hello Chief, I would like to work on this issue. I have 3 years of experience as an open source contributor

[grantfox-oss]

🦊 GrantFox — @OkeyAmy has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #20)
2. Your PR will be reviewed by the Chainmove maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@OkeyAmy's PR #58 was approved and merged by @Obiajulu-gif.

🏆 @OkeyAmy: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (153 total points). Track your full progress on GrantFox.

👏 Great work, @OkeyAmy! Keep contributing to Chainmove.