Migrate average-permutation-frontier-cs-algorithmic-124

[ifsheldon]

Frontier-CS migration: Average Permutation

• Source path: algorithmic/problems/124
• Challenge handle: average-permutation-frontier-cs-algorithmic-124
• Execution mode: piped_stdio
• Target: linux-arm64-cpu
• Solution contract: zip_project stdin/stdout

Public/private split

Public validation is a tiny synthetic interactive smoke session committed at v1/public/session.json. Official Frontier-CS-derived hidden input and answer files are packaged only in the private overlay at /home/maplespark/code/Agentics-private-overlays/average-permutation-frontier-cs-algorithmic-124/official-runs.zip under private-benchmark/session.json and private-benchmark/cases/.

Acceptance criteria

• python3 scripts/validate_challenges.py passes in the challenge worktree.
• The smoke solution under test-solutions/average-permutation-frontier-cs-algorithmic-124/ completes public piped_stdio validation locally.
• The private overlay ZIP contains no traversal or symlink entries.
• The public bundle contains no Frontier-CS official input or answer files.

Known risks

Agentics piped_stdio runs one participant process per evaluation, so official sessions chain the source testdata cases inside one stdin/stdout session while preserving each original Frontier-CS interactor protocol, hidden state, query limits, and scoring.

[ifsheldon]

Migration lifecycle completed for the temporary MVP publication path.

• Source: algorithmic/problems/124
• PR: Add average-permutation-frontier-cs-algorithmic-124 #334
• Published challenge: average-permutation-frontier-cs-algorithmic-124
• Target: linux-arm64-cpu
• Temporary Moltbook URL: https://www.moltbook.com/post/fake-average-permutation-frontier-cs-algorithmic-124
• Private backup prefix: private-bundle-backups/average-permutation-frontier-cs-algorithmic-124/
• Smoke submission: 72d9c3b6-fc9b-4067-9a84-1848e0fdf5d6, status completed
• Public observer checks: challenge detail, leaderboard, public submission, public result report, and Moltbook anchor were reachable.

Remaining TODO: replace the fake Moltbook URL with the real post URL.

[ifsheldon]

Official Moltbook tracker published:

https://www.moltbook.com/post/fbf2aeb3-acf5-4c2f-80c2-79f501dfcf69

Closing this migration tracking issue now that the public tracker exists.

[ifsheldon]

Reopening: the Moltbook tracker URL created in the scheduled publisher run did not verify as a public tracker. Authenticated readback returned verification_status=pending and is_spam=true, no verification challenge/code was available to solve, and the post was absent from the agentics-platform feed/search. The local tracker ledger/frontmatter have been reset to draft for retry; the hidden pending Moltbook post was submitted for deletion via the API.