Consolidate redundant tests across the entire suite

[david-hoffman]

The suite repeated fits, artifact installations, and verifier setup across tests that proved the same behavior. Consolidate these checks and remove weaker duplicates while preserving distinct numerical regimes, independent expected values, state preservation, and release/process safeguards.

Audited all 61 test modules. Removed 43 test functions and 83 pytest cases (1,932 → 1,849; 4.3%), with 593 net test lines removed. All eight doctests remain. Product code, tooling, workflows, discovery, and coverage policy retain their existing behavior. Consolidation slightly reduces failure granularity; independent review found no lost contract proof.

Current state

• Authorization/route: owner-requested entire-suite test audit and PR; routine maintenance with reused contracts, four authors including the coordinator, and one fresh independent reviewer. No new scenarios or specialist checkpoint.
• Candidate: 016d3f60554ee67ecaa1bfc541f5f348c86dae47, reviewed and unchanged, against 04cbac9b59fa695218ddbafb6978529eafd8a2bc on codex-main. Independent review accepted with no actionable findings.
• Verification: python tools/verification.py pr --base 04cbac9b59fa695218ddbafb6978529eafd8a2bc selected Tier 5 full/global across library, doctor, release, and verification. Every step passed fresh on macOS 27.0 arm64, CPython 3.13.15, with hash-locked dependencies. All 1,857 tests/doctests passed; zero failures, errors, or skipped tests. All 21 owned files and both packages have exact 100% statement/branch coverage: 3,421/3,421 statements and 902/902 branches, with zero missing, partial, or excluded counts. Earlier environment-only failures and 176 test warnings remain retained in local evidence.
• Environment: disposable standalone Python; PYTHON_CPU_COUNT=1, BLACK_NUM_WORKERS=1, and pip's supported externally-managed override scoped to that temporary runtime. Shell-hook statement/branch measurement remains unsupported.
• Blockers/next action: hosted Linux/macOS/Windows verification is pending; required-check protection remains unverified. Wait for CI before any integration decision. This request authorizes opening the PR; merge and publication are not authorized.
• Metrics: 0 new scenarios; author/reviewer launches 4/1; 4 subagent launches total; no specialist rounds or repairs; no spending cap supplied or reliable monetary meter. All attempts retained outside Git.

Audit record: docs/tasks/TEST-AUDIT-003.md.