[codex] refactor longbridge strategy registry metadata

[Pigbibi]

What changed

• refactor LongBridge strategy registry to use the shared UES platform-registry helper
• keep LongBridge-specific enabled/default profile ownership in the platform repo
• standardize README profile matrix wording and alias display

Why

This removes duplicated registry glue while keeping runtime behavior unchanged. Strategy definition stays in UsEquityStrategies; LongBridge still decides what is actually enabled.

Impact

• no strategy logic or parameters changed
• no runtime behavior changed
• alias resolution and profile matrix generation now come from the shared helper

Dependency

• Depends on UES metadata/helper refactor: [codex] refactor us-equity strategy metadata and platform registry support UsEquityStrategies#4
• Requirements pin updated to commit: 17fa78c22463070b88ba4a884c84e7a761835ccb

Validation

• pytest tests/test_runtime_config_support.py tests/test_strategy_loader.py