Add typed environment configuration validation

[Lakes41]

Difficulty: Hard

Type: Maintenance

Summary

Add a typed configuration layer for API URL, chain ID, app mode, and future mobile integration settings. This avoids silently falling back to production defaults when local or release configuration is missing.

Current Behaviour

guildPassClient reads apiUrl and chainId directly from Constants.expoConfig?.extra, falling back to https://api.guildpass.xyz and chain ID 8453. Settings reads similar values directly for display.

Expected Behaviour

App configuration should be parsed and validated once, then consumed through a typed module. Invalid values should fail clearly in development and use safe release defaults only when explicitly intended.

Suggested Implementation

Create a src/config/appConfig.ts module. Validate API URL format, numeric chain ID, app environment, and optional feature flags. Update SDK client creation and settings display to use the typed config.

Files or Areas Likely Affected

• src/lib/guildpassClient.ts
• app/settings.tsx
• app.json
• .env.example
• src/config/
• README.md

Acceptance Criteria

• API URL is validated before SDK client construction
• Chain ID is parsed as a finite number
• Settings screen reads config from a shared typed module
• Invalid config produces a clear developer-facing error
• .env.example documents supported values
• README explains local and release configuration setup

Additional Notes

Assumption: the current production API fallback is useful for demos but unsafe as an implicit default in all builds.

[xx7412421-cloud]

/claim #18

I can take this if it is still available.

Plan:

• inspect the existing environment access pattern first
• add a typed validation layer for required config values with clear failure messages
• run the relevant mobile/project checks before opening the PR

I will wait for assignment before submitting a PR.

[YfengJ]

I would like to apply for this issue.

If assigned, my plan is to add a typed appConfig boundary that parses Expo extra values once, validates API URL / numeric chain ID / app environment, and exports safe typed values for the SDK and settings UI. I would keep release defaults explicit, avoid changing runtime behavior outside config consumption, and include focused validation/tests or documented verification for valid config, missing dev config, invalid URL, and invalid chain ID cases.

[David-patrick-chuks]

Hi, I'd like to work on this issue. I've gone through the description and acceptance criteria and I'm confident I can deliver it. I'll make sure every acceptance criterion is met and submit a clean, tested PR. Please assign it to me.

[JenyferMontano]

I would like to work on this issue.

I use TypeScript and Expo, and I can set up the typed validation layer in src/config/appConfig.ts using Zod. I'll make sure it validates the API URL and Chain ID, throws a clear error in dev mode if something is missing, and update the docs.

[gloskull]

Hello, I have 4 years of experience delivering solutions for projects like this, covering backend, frontend, and smart contract development. After carefully reviewing your requirements, I have a clear understanding of the task and am confident in my ability to deliver a clean, efficient, and thoroughly tested solution on time. I prioritize code quality, maintainability, and industry best practices throughout the development process.
My PR will be submitted in under 10hours.