Complete EVM wallet workbench and harden mobile signing paths

[0xfnzero]

Summary

• Add the EVM wallet workbench and mobile EVM chain/token registry integration across desktop, Flutter, Rust services, and the FRB bridge.
• Harden Solana and EVM preview/confirm/submit flows with content-bound preview IDs, wallet/keystore matching, and stale preview rejection.
• Improve mobile dApp behavior by returning rejection responses reliably and supporting EVM provider connect/disconnect plus account and chain change events.
• Add defensive storage loading for mobile wallet metadata, custom EVM chains, and custom ERC-20 tokens.

Review fixes included

• Validate EVM preview IDs before decrypting keystores on payment and dApp submit paths.
• Ensure dApp rejection always resolves/rejects the WebView provider Promise instead of hanging after an expected UserRejected error.
• Regenerate Flutter/Rust bridge bindings after the DTO changes.

Tests

• ./apps/mobile/tool/generate_bridge.sh
• cargo fmt --all -- --check
• cargo check --workspace --all-features
• cargo test --workspace --all-features
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• dart format lib test
• flutter analyze
• flutter test --dart-define=FNZERO_MOBILE_DEV_BRIDGE=true
• npm run lint
• npm exec tsc -- --noEmit
• npm run build
• git diff --check