feat: add logging for channel auto-accept failures

[doitian]

Summary

This PR adds comprehensive logging for channel auto-accept failures to help operators understand why channels aren't being auto-accepted, making debugging easier when channel opening fails.

Changes

Refactoring

• Extracted UDT matching logic into a reusable find_matching_udt method in UdtCfgInfos to avoid code duplication
• Refactored get_udt_info in contracts.rs to use the new method
• Made get_udt_info public to enable logging functionality

Logging

• Sender-side logging: Added warnings when opening channels with insufficient funding amounts (CKB or UDT) that don't meet peer's auto-accept requirements
• Receiver-side logging: Added warnings when auto-accept fails for incoming channel requests, including:
  • Insufficient funding amounts
  • UDT types not configured for auto-accept
  • Auto-accept disabled scenarios
• All logging is conditional on tracing::Level::WARN being enabled to avoid performance overhead
• Added ChannelAutoAcceptFailed debug event when auto-accept fails

Testing

• Added comprehensive unit tests for find_matching_udt covering:
  • Exact match scenarios
  • Regex pattern matching
  • Wrong code_hash, hash_type, and args
  • Multiple UDTs in whitelist
  • Empty whitelist
• Added integration test test_auto_accept_fails_debug_event to verify debug event is triggered

Benefits

• Operators can now easily diagnose why channels aren't being auto-accepted
• Reduces debugging time by providing clear, actionable log messages
• Helps identify configuration mismatches between peers
• Maintains performance by only logging when WARN level is enabled