Phase 559: refresh annotation store implementation queue

[ExplodingUFO]

Summary

• record Phase 559 as the post-annotation-store contract implementation queue refresh in both parity roadmap locales
• add tracker-backed Phase 560-564 queue rows and recommended worktree guidance
• add focused docs regression coverage for the Phase 559 roadmap contract

Verification

• dotnet test tests\AsterGraph.Demo.Tests\AsterGraph.Demo.Tests.csproj -c Release --filter "FullyQualifiedName~ReactFlowParityRoadmapDocsTests.ParityRoadmapDocs_RecordPhase559AnnotationStoreImplementationQueueRefreshInBothLocales" --no-restore --verbosity minimal (1/1 passed)
• dotnet test tests\AsterGraph.Demo.Tests\AsterGraph.Demo.Tests.csproj -c Release --filter "FullyQualifiedName~ReactFlowParityRoadmapDocsTests" --no-restore --verbosity minimal (59/59 passed)
• dotnet test tests\AsterGraph.Demo.Tests\AsterGraph.Demo.Tests.csproj -c Release --no-restore --verbosity minimal (304/304 passed)
• dotnet build AsterGraph.sln -c Release --verbosity minimal (0 warnings, 0 errors)
• git diff --check (exit 0; line-ending warnings only)

Stack

• Base: feature/phase-558-whiteboard-annotation-store-contract-skeleton / PR Phase 558: internal whiteboard annotation store contract skeleton #240
• Blocks: Phase 560-564 follow-up execution
• Do not merge before Phase 558 clears the lower stack

[ExplodingUFO]

Final restack verification for PR #247 after PR #240 was rewritten:

• Base: a1872e805c4ea560317eff48afa57cf0e58ac006 (feature/phase-558-whiteboard-annotation-store-contract-skeleton)
• Head: d13318e6dea0fe230c5609870938c4862a00c3a4 (docs/phase-559-annotation-store-implementation-queue)
• git range-diff e2a817c..backup/phase-559-before-restack-20260514 a1872e8..HEAD confirms the single Phase 559 docs/tests commit is equivalent after restack.

Local verification in .worktrees/phase-559-annotation-store-implementation-queue:

• dotnet test tests\AsterGraph.Demo.Tests\AsterGraph.Demo.Tests.csproj -c Release --filter "FullyQualifiedName~ReactFlowParityRoadmapDocsTests" -> 59/59 passed
• dotnet build AsterGraph.sln -c Release --no-restore -> 0 warnings, 0 errors
• dotnet test tests\AsterGraph.Demo.Tests\AsterGraph.Demo.Tests.csproj -c Release --no-build -> 304/304 passed
• git diff --check a1872e805c4ea560317eff48afa57cf0e58ac006..HEAD -> clean

GitHub remote verification is now MERGEABLE / CLEAN; all duplicate checks passed: hygiene-proof, framework-matrix net8.0/net9.0/net10.0, linux-validation, macos-validation, contract-proof, and release-validation.

PR remains blocked only for stacked merge ordering behind Phase 558 / PR #240 and the lower stack.