feat: GF-T 2-input on-chip trainer primitive (proven on AX7203)

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New spec gft_train2.t27 — on_comb(w0,w1,x0,x1,t,eta) -> u64 runs one full on-chip SGD step of a 2-input linear neuron y=w0x0+w1x1 (forward, error, grads g_i=ex_i, updates w_i-etag_i), returning both updated weights packed (w0'<<32)|w1'. Reuses gft_sgd_step helpers. In-spec PASS, iverilog bit-exact. Proven on a live AX7203 (uart_train2.v): with both weights in registers the whole forward+backward+update runs on-chip; streaming a hidden function w*=(1.0,0.5) the board discovers BOTH params (w0 0.25->1.03, w1 0.25->0.48). docs/NOW.md updated. Refs #1764

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Generated at: 2026-08-07 00:20:02 UTC

• feat: GF-T 2-input on-chip trainer primitive (proven on AX7203) #1818 feat: GF-T 2-input on-chip trainer primitive (proven on AX7203) | Created: 2026-08-07 | Updated: 2026-08-07 | 10 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).