Release wave: QUBODrivers 0.3→0.6 / QUBOTools 0.10→0.13 + timing metadata

[bernalde]

Part of the benchmarking-readiness epic: JuliaQUBO/QUBO.jl#40 (WS2 — coordinated driver release wave). Blocked by the QUBODrivers metadata/seed standardization and conformance-suite issues on that epic (WS1) — adopt both in a single PR here so the package is only touched once.

Problem

QUBO.jl v0.6 requires QUBODrivers = "0.6" / QUBOTools = "0.13". TenSolver.jl's current compat is:

QUBODrivers = "0.3"
QUBOTools   = "0.10"

The intersection with QUBO.jl v0.6 (and with the QUBOLib-served QOBLib benchmarking stack) is empty — this package cannot be installed alongside the rest of the ecosystem. A scheduled ecosystem-resolution canary is being added to QUBO.jl that will stay red until this lands.

Package-specific work

• Largest version jump in the wave: QUBODrivers 0.3 → 0.6 and QUBOTools 0.10 → 0.13. Expect API churn (the @setup macro surface and SampleSet constructors changed); budget accordingly. If anything is unclear, MQLib.jl post-wave is the reference implementation.
• No timing recorded in SampleSet metadata — DMRG elapsed time is only logged via the ITensors on_iteration callback. Capture it (sweep times + total) into metadata["time"]["effective"] and the namespaced breakdown.
• DMRG convergence parameters (maxdim, cutoff, vtol) are the natural sweep axes — expose them as typed @setup attributes.
• Recently fixed one-variable QUBO handling (Modernize Julia CI cache action and workflow pins #48) — make sure that fix is in the release that carries the compat bump.

Common work (all drivers in the wave)

1. Bump compat: QUBODrivers = "0.6" (drop pre-0.5 entries unless there's a reason to keep them) and QUBOTools = "0.13" where it is a direct dependency. Fix any breakage from the upgrade.
2. Adopt the QUBODrivers metadata schema: metadata["time"]["effective"] (backend solve time) always set; seeds recorded under metadata["seeds"]; backend name/version under metadata["backend"].
3. Declare capability traits honestly (supports_seed, honors_final_reads, enforces_time_limit).
4. Adopt the standard RandomSeed attribute where the backend supports seeding (alias any existing seed attribute to it; keep the old one as deprecated).
5. CI runs the upgraded QUBODrivers.test(Optimizer) with benchmark_conformance = true.
6. Tag a release and verify it registers (General registry compat must match).

Checkpoints (anti-drift)

• Before starting: wait for the reference driver run posted on the epic (first wave driver, suggested MQLib.jl) and use its conformance output as the template — deviations should be deliberate, not accidental.
• Mid-PR: post the conformance-suite output here (all sets, including which are trait-skipped and why).
• Before merge: resolve a temp environment with QUBO@0.6 + this branch via Pkg.develop — the actual coexistence check, not just compat-file edits.

Acceptance criteria

• Registered release with QUBODrivers 0.6 / QUBOTools 0.13 compat, conformance suite green in CI, package resolves alongside QUBO.jl v0.6.

[bernalde]

Reference driver checkpoint is ready enough to start this package's wave PR.

MQLib status:

• Add QUBODrivers 0.6 benchmark conformance JuliaQUBO/MQLib.jl#27 merged into main.
• Reference checkpoint posted on the epic: Epic: Benchmark-ready JuliaQUBO ecosystem for the QOBLib campaign JuliaQUBO/QUBO.jl#40.
• MQLib release-prep PR Prepare v0.7.0 release JuliaQUBO/MQLib.jl#28 is open, CI-green, and bumps the release to v0.7.0; registration is still pending.
• Final reference stack uses QUBODrivers = "0.6.1" and QUBOTools = "0.13".
• Reference conformance result: supports_seed=true, honors_final_reads=true, enforces_time_limit=true, Benchmark Conformance 14/14, no trait-skipped benchmark sets.

Implementation guidance for TenSolver.jl:

• Target QUBODrivers = "0.6.1" and QUBOTools = "0.13".
• Expect real API migration work because this jumps from QUBODrivers 0.3 to 0.6 and QUBOTools 0.10 to 0.13; MQLib.jl#27 is the closest current reference implementation.
• Capture DMRG elapsed time into metadata["time"]["effective"]; preserve sweep-level timing under a namespaced breakdown.
• Promote campaign sweep axes such as maxdim, cutoff, and vtol to typed setup attributes.
• Include the one-variable QUBO fix in the release that carries this compat bump.
• Declare seed/read/time-limit traits honestly; if deterministic seeding is unavailable, use supports_seed = false.

Use MQLib.jl#27/#28 as the reference shape: compat bump, metadata schema, trait declarations, unconditional QUBODrivers.test(...; benchmark_conformance = true), conformance transcript, QUBO v0.6 coexistence check, then release/registration.

[bernalde]

Package-side release wave is complete. TenSolver v0.2.0 is published at https://github.com/SECQUOIA/TenSolver.jl/releases/tag/v0.2.0 and registered in General. Registered compat for the 0.2 series includes QUBODrivers = "0.6.1 - 0.6" and QUBOTools = "0.13". The branch also adopted the QUBODrivers metadata/conformance work and CI is green on the release commit. Downstream ecosystem resolver failures should now be tracked in the affected downstream packages rather than this TenSolver release issue.