[Docs] Rewrite README to match the actual stack and document env vars

[grantfox-oss]

Telegram (ask questions / claim the issue here first): https://t.me/+DOylgFv1jyJlNzM0

Why this matters

The README marks Stellar wallet integration, state management, and dark mode as planned, but the code already ships Freighter, Zustand stores, and a theme store with dark mode. New contributors are misled. The .env.example keys are also undocumented.

Acceptance criteria

• Update Tech Stack, Features, Wallet Integration, and State Management sections to reflect what is implemented
• Document every variable in .env.example with purpose and example value
• Fix Available Scripts to match package.json after the scripts issue lands
• Remove or clearly mark sections that are genuinely future work

Files to touch

• README.md
• .env.example

Out of scope

• Architecture deep-dive doc (separate)

[Miracle656]

Hi team 👋

I'd like to work on this! I'll update the Tech Stack, Features, Wallet Integration, and State Management sections in README.md to reflect what's actually implemented (Freighter, Zustand, dark mode), document every .env.example variable with purpose and example value, and clearly mark genuinely future work as such.

Estimated delivery: 1 day. Please assign it to me 🙌

[Spagero763]

i would like to take up the issue

[akprinciple]

Dear kindly assign this issue to me

[sankie13]

Hi! I would like to contribute to this issue.

I have experience working with software projects using Java, .NET and Python, and I am interested in contributing to open source by improving documentation quality and developer onboarding.

I can help update the README so it accurately reflects the current implementation, including the real tech stack, wallet integration, state management, and available features. I can also document the environment variables from the .env.example file with clear descriptions and example values.

My approach would be to verify the documentation against the actual codebase and package configuration, keeping the changes accurate and easy for new contributors to follow.

[grantfox-oss]

🦊 GrantFox — @akprinciple 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 #15)
2. Your PR will be reviewed by the LabsCrypt maintainers

Good luck! Track your progress on GrantFox.