✨ Support iteration over OpenQASM arrays and slices

[simon1hofmann]

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Description

Support for loops over one-dimensional classical arrays and slices, including
rank-one selections from multidimensional arrays and runtime slice bounds.

• Bind each element by value in a local loop variable. Assigning the variable
  does not change the array or the next iteration value.
• Capture slice bounds once, read elements in selection order, and preserve
  nested break/continue and empty-array behavior.
• Reuse existing views, loop lowering, initialization checks, and scalar type
  conversions. Do not copy or unroll the iterated array.
• Support bool, sized int/uint, float, and compatible angle loop variables.
  Retain the existing restrictions on runtime fixed-width angle conversion.

Stacked on #2585. Refs #2109; this intermediate slice does not close the issue.
Subroutines and array-reference parameters remain separate work.

Validation

• At this PR boundary, all 213 frontend/emitter, 239 compiler, 204 native QCO, and 219 QC translation tests pass.
• Execution checks cover QC/QCO round trips, Adaptive QIR, measurement-dependent bounds, reversed slices, nested jumps, narrow integer conversions, and by-value iteration.
• Full-file C++ lint found no issues in this PR's changed files. Repository lint and diff-whitespace checks pass.
• Hosted CI for the pushed commits has not been checked.

Codex assisted with implementation, tests, documentation, and this description.

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the CI checks.
• I have reviewed my own code changes.

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• I have disclosed AI assistance in the PR description.
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[codecov]

Codecov Report

❌ Patch coverage is 96.39640% with 8 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...nclude/mqt/Target/OpenQASM/Detail/OpenQASMParser.h	89.7%	4 Missing ⚠️
...lib/Dialect/QC/Translation/OpenQASMToQCEmitter.cpp	96.6%	2 Missing ⚠️
mlir/lib/Target/OpenQASM/OpenQASMSemantics.cpp	98.3%	2 Missing ⚠️

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