Improve ConsolidateBlocks error messages for NaN/Inf gate parameters

[Pranava-Kumar]

Summary

When a circuit contains gates with NaN or Inf parameters, ConsolidateBlocks currently fails with a non-descript NoConvergence error (from scipy's eigenvalue decomposition in the Weyl decomposition), giving no indication of the root cause. This makes debugging circuits with invalid parameters very difficult.

This PR:

1. Detects NaN/Inf in gate matrices before attempting decomposition and raises a clear error with block context
2. Adds block context (gate names, parameters, qubit indices) to existing decomposition errors

Before

QiskitError: 'NoConvergence'

After

QiskitError: 'ConsolidateBlocks failed because the 2-qubit block contains a circuit gate with NaN or Inf parameters: rz(nan) on qubits [0]; cx() on qubits [0, 1]'

Related Issues

Fixes #16236

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