Solana Pay integration

[chainsona]

Problem

Gill lacked Solana Pay support, preventing developers from creating payment URLs and merchant integrations.

Summary of Changes

Adds comprehensive Solana Pay support with a zero-dependency implementation built from scratch.

Core Implementation:

• Types - Clean interfaces for transfer/transaction requests with TypeScript support
• Functions - Complete Solana Pay spec implementation using decimal amounts
• Features - URL creation, parsing, validation, QR codes, and reference tracking

Key Functions:

• createTransferRequestURL() - SOL and SPL token payments
• createTransactionRequestURL() - Interactive payment flows
• parseSolanaPayURL() - Extract payment details from URLs
• validateSolanaPayURL() - Robust URL validation
• toQRCodeURL() - QR code generation for mobile wallets

Examples:
Four progressive examples (01-basic.ts through 04-wallet.ts) demonstrating usage patterns from basic transfers to complete wallet integration.

Technical Details:

• Zero external dependencies - uses only gill's utilities and standard web APIs
• Decimal amount support per Solana Pay specification
• Full TypeScript support with gill's Address types
• Concise 140-line implementation with natural, readable code

Fixes #127

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5486769

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[vercel]

@chainsona is attempting to deploy a commit to the Solana Foundation Team on Vercel.

A member of the Team first needs to authorize it.

[nickfrosty]

Your code feels heavily ai generated and will not be accepted.
installing and importing the original solana pay package and web3js defeats the purpose

[chainsona]

I understand your concern. I use AI to generate supporting content around the actual code implementation (eg. documentation, inline comments, test case).

Here a new implementation, with no external dependencies to other solana libs.