[Bug] `frontend/src/types/env.d.ts` still declares Vite's `ImportMetaEnv`/`VITE_*` types

[Dev-AdeTutu]

Verified against source in the session that drafted this issue (not just inferred).

Describe the Bug
The type declaration file documents VITE_CONTRACT_ID, VITE_BACKEND_URL, VITE_NETWORK_PASSPHRASE, VITE_SMS_SHORTCODE, VITE_SMS_WEBHOOK_DOCS, VITE_API_URL, VITE_RPC_URL as the env contract for this app — none of which are read correctly at runtime (root cause of #5–#9).

Steps to Reproduce

1. Open frontend/src/types/env.d.ts.
2. Compare against actual process.env.NEXT_PUBLIC_* reads across the codebase (contract.ts, fetchWithTimeout.ts, dashboard pages, etc.) — they don't match.

Expected Behavior
Type declarations match the real env contract and give contributors/IDE autocomplete correct guidance.

Actual Behavior
Actively misleading — this file is likely why #5–#9 exist, since it presents VITE_* as the correct pattern.

Guidelines

• Fix this file as part of the same PR that fixes chore: add CONTRIBUTING.md and issue/PR templates #5–bug: handle Freighter wallet not installed gracefully #9, or immediately after, so the misleading reference doesn't cause a recurrence.
• Consider replacing the ambient type declaration entirely with the validated env module proposed in FE-47.

Definition of Done

• ImportMetaEnv/VITE_* declarations removed
• Real NEXT_PUBLIC_* contract documented (via types or the FE-47 validated module)
• Cross-referenced with chore: add CONTRIBUTING.md and issue/PR templates #5–bug: handle Freighter wallet not installed gracefully #9 fixes

[nextgenuniversity1-oss]

@nextgenuniversity1-oss has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi! I'd like to work on this issue. I understand the requirements and will implement the requested changes while following the project's guidelines. I'll test the solution thoroughly, ensure it passes all required checks, and submit a clean PR with a clear description of the changes.

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[SMOGZ6783]

@SMOGZ6783 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

please can u let me handle this issue

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[dot-enny]

@dot-enny has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I'll handle this ASAP ETA - 1hr once assigned.

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[drips-wave]

Congratulations, @orbitlumen-hue! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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