Refactor: Move Provider Operations onto Provider Handles

[sephynox]

Summary

This PR update returns a provider handle bound to its client, and all per-provider operations and metadata queries live on that handle, matching how the TypeScript and Rust clients are used.

Related Issues

• Feature: Certificate Writes and Native X.509 Bridge #16
• Feature: Ledger Reads, Builder Publishing, and Network Presets #13
• Feature: Basic Network Operations #12
• Feature: Signer-Bound UserClient #11
• Feature: Block Building and Fee-Aware Transmit #10
• Feature: Base Updates from anchor-rs v0.4.0 #9

Changes Made

• GetProviders and friends return AssetProvider / KycProvider handles
• Transfers, forwarding, KYC sharing, and verification run on the handle
• client.Provider(info) rebinds a stored snapshot to a live client
• Disclaimers, anchor details, and token metadata parse on the info record
• AssetSimulatedTransfer and AssetTransfer follow-ups route via their provider

Testing

• make test: passes

Breaking Changes

• The AssetProvider and KycProvider records are now AssetProviderInfo and KycProviderInfo
• Replace client.Operation(provider, ...) with provider.Operation(...)
• The GetProviderAnchorDetails is now GetAnchorDetails on the handle.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
96.2% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud