**feat: user-extensible chain management + 5 new built-in chains**

[AmpedFinance]

Description

This PR adds the ability for AI agents to add custom EVM chains through natural language, and includes 5 new built-in chains commonly used in DeFi.

What's New

🆕 New Commands (Agent-Friendly)

Command	Description
node src/add-chain.js <name> <chainId> <rpc>	Add a custom chain
node src/list-chains.js	List all available chains
node src/remove-chain.js <name>	Remove a user-defined chain

All commands support --json for machine-readable output, making them ideal for AI agent integration.

🔗 5 New Built-in Chains

Chain	Native Token	Chain ID	Notes
Sonic	S	146	Sonic mainnet
LightLink	ETH	1890	Legacy gas pricing
HyperEVM	HYPE	998	Hyperliquid EVM
Avalanche	AVAX	43114	C-Chain
BSC	BNB	56	BNB Smart Chain

🛠️ User-Extensible Chains

Users can add any EVM chain without waiting for a new release:

# Add Berachain
node src/add-chain.js berachain 80094 https://rpc.berachain.com --native-token BERA --explorer https://berascan.io

# Add a chain with legacy gas (non EIP-1559)
node src/add-chain.js mychain 12345 https://rpc.mychain.io --legacy-gas

Custom chains are stored in ~/.evm-wallet-chains.json and persist across sessions.

🤖 AI Agent Integration

When a user tells their agent:

"Add Berachain with chain ID 80094 and RPC https://rpc.berachain.com"

The agent can run:

node src/add-chain.js berachain 80094 https://rpc.berachain.com --native-token BERA --json

This enables natural language chain management — users don't need to manually edit config files.

Technical Details

• chains.js now loads user-defined chains from ~/.evm-wallet-chains.json and merges them with built-in chains
• Added isLegacyGasChain() helper for chains that don't support EIP-1559 (e.g., LightLink)
• legacyGas: true flag in chain config triggers legacy gas pricing
• Updated Polygon RPCs to more reliable endpoints

Files Changed

src/lib/chains.js    - Extended with 5 chains + user chain loading
src/add-chain.js     - NEW: Add custom chains via CLI
src/list-chains.js   - NEW: List all available chains  
src/remove-chain.js  - NEW: Remove user-defined chains
README.md            - Updated documentation
SKILL-clawdhub.md    - Updated skill definition with new commands

Backward Compatibility

✅ Fully backward compatible — existing functionality unchanged
✅ All original chains preserved
✅ No breaking changes to existing commands

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Testing

# List all chains
node src/list-chains.js

# Add a test chain
node src/add-chain.js testchain 99999 https://rpc.test.io --native-token TEST --json

# Verify it was added
node src/list-chains.js --json

# Remove the test chain
node src/remove-chain.js testchain --yes

# Check balance on new built-in chain
node src/balance.js sonic

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Related

This enhancement was developed to support Amped Finance's OpenClaw plugin, which uses evm-wallet-skill for DeFi operations across multiple chains.

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Checklist

• New commands support --json output
• SKILL-clawdhub.md updated with new tools
• README updated with new chains and commands
• Legacy gas support for non EIP-1559 chains
• User chains persist in ~/.evm-wallet-chains.json
• Tested locally