feat: GF-T 2-neuron hidden layer on-chip trainer (proven on AX7203)

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New spec gft_hidden2.t27 — on-chip SGD step of a 2-neuron hidden layer y=relu(w0x0)+relu(w1x1) (fixed unit output weights). Two INDEPENDENT nonlinear units, each with its own relu gate; per-neuron gated gradient dw_j=e*relu'(z_j)x_j; updates w_j-etadw_j; returns (w0'<<32)|w1'. In-spec tests (both/onedead) PASS. Proven on a live AX7203 (uart_hidden2.v): the units gate INDEPENDENTLY — killing one neuron's activation freezes only its weight while the other keeps learning (MOVED vs FROZEN across 3 phases). docs/NOW.md updated. Refs #1764

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Generated at: 2026-08-07 00:58:14 UTC

• feat: GF-T 2-neuron hidden layer on-chip trainer (proven on AX7203) #1820 feat: GF-T 2-neuron hidden layer on-chip trainer (proven on AX7203) | Created: 2026-08-07 | Updated: 2026-08-07 | 11 failing / 15 total
• feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1815 feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 1 total
• feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1813 feat(igla): Wave Loop 882 — module-scope [583][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total
• feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes #1810 feat(igla): Wave Loop 881 — module-scope [581][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes | Created: 2026-08-06 | Updated: 2026-08-06 | 0 failing / 12 total

Summary

Status	Count
Total Open PRs	4
PRs with Failing Checks	0
PRs with All Checks Green	4
READY	3
FAILING	0
PENDING	0

Seal Status

• ⚠️ STALE -- sha256(compiler.rs)=4c1aaad5309a != manifest seal=87e5cbd3ad94.
  The committed NMSE numbers were certified against an older compiler.rs.
  Run scripts/reseal-check.sh locally for the two-step reseal command (advisory; not a merge gate).