Test audit 1: delete digest pins, type-size recomputations, unrun tests and scalar-oracle pairing tests

[tamashi095]

Test audit 1: delete digest pins, type-size recomputations, unrun tests and scalar-oracle pairing tests

Closes #1722

The owner approved four test categories for deletion without mutation proof (2026-10-18), as the first phase-B cut of the 2026-10 test audit (owner: "Don't you think almost 50% of codebase being tests is overboard?"). Each deleted test is listed with its category and line count in .github/ISSUE_SPECS/1722-delete-digest-type-size-and-unrun-tests.md.

What changed

• (a) Digest and byte-count pins outside the AGENTS.md "Test value" classes (wire, ABI, on-disk formats, the single cross-target corpus owner): 5 items, about 330 lines.
• (b) Exact size_of recomputations: 9 tests trimmed in place. Real resource ceilings and ABI layouts stay.
• (c) Ignored timing lines that assert nothing, and ignored sweeps that no workflow runs: 9 tests, about 385 lines.
• (d) Scalar-oracle pairing tests (Keep the whole-plan scalar backend as a test-only oracle, out of shipped builds #1059): 17 of 20 tests and their helpers, 2,328 lines. The scalar oracle itself stays as a reference.
• 19 files; about -4,070 / +990 lines. No product code changed.

Review

One adversarial verifier: READY WITH FIXES, with 2 majors. Two real estimator relations had been cut together with the size_of code: the graph-compiler runtime-metadata charge and the graph activity-offsets charge (#1652). Both are restored as relations, and each one is red on its mutant (448 vs 492; 4096 vs 4124). Four minors are fixed. The re-check gave READY.

Evidence

fmt, clippy -D warnings, the tests of the 11 touched packages (1,786 passed; 359 again after the fold) and check-workspace-policy.sh all pass locally. CI is the first full independent build.

Kept for an owner decision (not cut here)

• The 3 scalar-oracle tests that are the only readers of SCALAR_INITIAL_MATRIX_TRACE.
• The math EXP2/LOG2 digest, which is the native witness of the AArch64 expected failure Make the compressor's AArch64 release build bit-identical to the browser (LANE-3) #1019.
• host-core limiter_linked_session PIN, which declares itself a cross-target corpus owner.
• gain_pan_profile phase_profile: no workflow runs it, but it is the only user of the graph phase-profile probes.
• One-line size_of counts inside larger tests.

🤖 Generated with Claude Code

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