⬆️ Replace private DDSIM capability metadata after QDMI standardization

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Elevator pitch

Remove temporary provider-specific metadata only when the public QDMI interface can express the same simulator capabilities without weakening compiler correctness.

Current state

The DDSIM device and target adapter use private all-to-all and controlled-operation metadata. Core supports zero-arity gphase and controlled standard-gate families; unknown target facts fail early.

Work and decisions

• Wait for the parent contract decision and inventory every private-property producer/consumer.
• Adopt the agreed public properties in DDSIM, the Client/bindings, and target inference.
• Remove private fallbacks only when the supported dependency baseline guarantees the replacement.
• Preserve arbitrary controls across supported standard gates, control polarity, zero-arity phase, and explicit topology.
• Update the glossary, target documentation, and workaround-removal notes.

Dependencies and release boundary

Blocked by 💡 Standardize simulator topology and controlled-operation capabilities. Core 4.1 candidate only if the public contract is settled; otherwise keep the current documented workaround.

Acceptance and validation

• Compiler/simulator tests preserve global phase and multiple controlled gate families, not just mcx/mcp.
• Unknown topology and gate-set metadata still fail during inference.
• Supported older dependency paths retain documented behavior until the minimum is raised.
• Run focused target/DDSIM tests, generated stubs where affected, docs, full lint, and cpp-lint.

Non-goals

Inventing a competing private extension; relaxing fail-closed inference; requiring Braket simulator parity for v4.0.

Scalability and phase tests

Verify that adopting the public metadata does not materialize quadratic all-to-all connectivity or enumerate every controlled-gate arity. Test multiple controlled standard-gate families and true zero-arity global phase using phase-sensitive state or unitary comparisons; sampled probabilities alone cannot verify global phase.