feat: Add Algorand + Voi chain support

[chopmob-cloud]

Summary

Request to add Algorand and Voi as supported chain families in OWS.

Chain Details

Property	Algorand	Voi
CAIP-2	algorand:mainnet-v1.0	algorand:voimain-v1.0
BIP-44 coin type	283 (SLIP-44)	283 (shared)
Curve	Ed25519	Ed25519
Address format	58-char base32 (SHA-512/256 checksum)	Same as Algorand
Native asset	ALGO	VOI
ASA support	Yes (Algorand Standard Assets)	Yes

Why

• Ed25519 signing — same curve as Solana, Sui, TON (already supported)
• x402 compatibility — a working x402 implementation for AVM chains already exists in AlgoVoi, following the same x402 protocol spec as ows-pay
• Two networks, one signer — Algorand and Voi share the same key derivation and address format, so a single algorand.rs signer covers both
• AVM ecosystem — Algorand has established DeFi (Tinyman, Pact, Folks Finance), NFTs (ALGOxNFT), and name services (ENS-style .voi via Envoi)

Implementation Scope

1. ows-signer/src/chains/algorand.rs — Ed25519 signer, base32 address encoding with SHA-512/256 checksum
2. ows-core/src/chain.rs — Add Algorand to ChainType enum + KNOWN_CHAINS
3. ows-core/src/caip.rs — Register algorand:* CAIP-2 namespace
4. Documentation update in docs/07-supported-chains.md

Happy to contribute the PR if there's interest.

Reference

• Algorand SDK (algosdk)
• AlgoVoi Chrome Extension — x402 + MCP + WalletConnect on AVM
• SLIP-44 coin type 283
• ARC-0001 (Algorand wallet spec)

[emg110]

Hey chopmob-cloud
The PR  to OWS (Open Wallet Standard) has been sent:
#124

Full report here: https://gist.github.com/emg110/06f371d06c4dff4ff8d42d7bdf24bdac