Dynamic RPC endpoints: chain registry, Keplr fallback, user settings

[saint-Joy]

Problem

All external chain RPC endpoints are hardcoded in src/utils/networkListIbc.ts. If any RPC provider goes down or gets blocked (e.g. by country-level firewalls), the bridge for that chain breaks completely.

Current hardcoded RPCs:

• osmosis: rpc-osmosis.ecostake.com
• cosmoshub: rpc.cosmoshub-4.bronbro.io
• juno: rpc-juno.itastakers.com
• evmos: rpc.evmos-9001-2.bronbro.io
• etc.

Proposed solution

1. Fallback RPC list

Multiple RPC endpoints per chain with automatic failover on connection error or timeout.

2. Chain registry integration

Use Cosmos Chain Registry as a source of up-to-date RPC endpoints. Can be fetched at app startup.

3. Keplr chain info

keplr.getChainInfosWithoutEndpoints() is already used in the codebase — extend to also extract RPC endpoints from Keplr's registry.

4. User-configurable RPC (Avatar Settings skill)

Create a skill in Avatar Settings where users can manually set custom RPC endpoints per chain. This is critical for users in countries where certain RPCs are blocked without VPN.

UI: Settings → Network → per-chain RPC input fields with "test connection" button.

Files to modify

• src/utils/networkListIbc.ts — replace static config with dynamic resolution
• Avatar Settings — new RPC management skill
• Consider localStorage persistence for user RPC preferences