The missing term was unary: omit-size solved at its ceiling in 1.4s

Adversarial review of the artifacts found three of my numbers to be
artifacts of my own code. All three reproduced here before acceptance:

- anchor_bound presented probe rows in the same index order on both
  sides, so exact twins had their tie broken onto the diagonal. 0.997 ->
  0.920 on omit-size. Fixed by scrambling the T-side presentation.
- The truth is not a strict local minimum: 51 transpositions have
  exactly zero energy delta. fast_pair_descent only looked stationary
  because its break test treats zero as no-improvement.
- scipy's FAQ takes no n_init, so it was swallowed into unknown_options
  and 'FAQ x30 restarts' computed bit-identically to plain FAQ. Replaced
  with a real restart loop over P0='randomized'.

The blind ceiling for omit-size is 0.836, not 1.0: the text field has 51
exact transposition automorphisms, so T[s,s] is bitwise identical to T
and no objective f(V, P T P^T) can separate an orbit at any order. Every
synthetic accuracy was being divided by the wrong denominator.

The fifteen failed solvers share one property -- all purely quadratic or
purely spectral, none with a node-level term. Eight moments of each
node's own field row, blended with the quadratic term through
Frank-Wolfe, reach 0.837 with an energy gap of exactly zero. The term
must stay in the loop: as a seed for pure-quadratic descent it scores
0.21, pinned through the iterations it scores 0.84 -- which is also why
amplification plateaued, being itself pure-quadratic.

Co-Authored-By: Claude <noreply@anthropic.com>

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diff --git a/artifacts/spectral_frontier_probe/eval_voteanchor_seed7.log b/artifacts/spectral_frontier_probe/eval_voteanchor_seed7.log
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+150 ICP solutions in 222s
+lowest-8 (E, acc, r): [(0.6733, 0.008, 8), (0.6824, 0.027, 10), (0.6956, 0.031, 10), (0.6988, 0.016, 8), (0.7011, 0.074, 12), (0.7026, 0.023, 10), (0.7052, 0.004, 10), (0.7052, 0.012, 8)]
+mean pairwise agreement among top-30: 0.046
+
+--- ROUTE A (free readout of the same ensemble) ---
+  best-E member acc 0.008 -> after exact descent acc 0.012  E=0.6565  [5s]
+  descend 5 lowest-E, pick by energy: acc 0.043  E=0.6316
+
+--- ROUTE B (the proposal) ---
+  m= 5 K= 12 kept= 12 precision=0.167 -> expansion acc 0.039 -> after descent 0.039
+  m= 5 K= 25 kept= 25 precision=0.080 -> expansion acc 0.031 -> after descent 0.051
+  m= 5 K= 50 kept= 47 precision=0.064 -> expansion acc 0.031 -> after descent 0.023
+  m= 5 K=100 kept= 91 precision=0.044 -> expansion acc 0.031 -> after descent 0.023
+  m=10 K= 12 kept= 12 precision=0.250 -> expansion acc 0.043 -> after descent 0.074
+  m=10 K= 25 kept= 23 precision=0.130 -> expansion acc 0.035 -> after descent 0.043
+  m=10 K= 50 kept= 48 precision=0.104 -> expansion acc 0.059 -> after descent 0.066
+  m=10 K=100 kept= 87 precision=0.069 -> expansion acc 0.035 -> after descent 0.035
+  m=30 K= 12 kept= 12 precision=0.417 -> expansion acc 0.094 -> after descent 0.180
+  m=30 K= 25 kept= 25 precision=0.320 -> expansion acc 0.141 -> after descent 0.125
+  m=30 K= 50 kept= 48 precision=0.229 -> expansion acc 0.215 -> after descent 0.816
+  m=30 K=100 kept= 80 precision=0.188 -> expansion acc 0.148 -> after descent 0.195
+
+E(truth)=0.3396   total wall 617s