Add control-flow checks to Rust check_map

[Sonai124]

Fixes #16118

Summary

• Make the native Rust run_check_map recurse through control-flow blocks.
• Compose nested control-flow qubit mappings before checking target connectivity.
• Add Rust unit tests for top-level, control-flow, remapped, and nested control-flow checks.

Tests

• cargo test -p qiskit-transpiler --lib
• uv run --group build --group test python -m unittest test.python.transpiler.test_check_map

AI/LLM disclosure

• I didn't use LLM tooling, or only used it privately.
• I used the following tool to help write this PR description: ChatGPT, GPT-5.5 Thinking.
• I used the following tool to generate or modify code: ChatGPT, GPT-5.5 Thinking.

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