Strict lockstep over-reported: the operand hook misses any op whose operands
aren't fetched via vm_operand_fetch (comment 0x1a7, set-string 0x192, the
0x1c7/0x1cc/0x131/... string-op cluster) — the engine executes them (they sit
after non-branching ops) but they're absent from its trace. New align() resyncs
over such one-sided insertions and reports only NON-realignable forks; it
separates VM-only blind spots (artifacts) from engine-only detours (real,
reconverging branch/state gaps, surfaced honestly). +2 tests (7/7).
Result: with G[0x6c1] seeded the SC0000 opening has NO non-realignable fork
across all 539 VM ops (was: false 'diverge at 0x8d'); residual = a 2-op
engine-only color detour (0x202/0x203 @ 0x122d0). Cold's first real fork is a
later G[0x6c1] gate. Validates the pre-scene-state theory end-to-end.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Operand-hook captures skip zero-operand ops (stmt markers, script-entry 0x259),
so the VM offset trace is filtered to argc>=1 instructions before diffing — same
subsequence both sides. +1 unit test. Default on; --full for a tick-mode capture.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Pure first_divergence + pick_scene_codebase (longest-common-prefix codebase
identification), unit-tested (test_diff_optrace.py, 4/4). CLI loads the engine
jsonl + VM json, isolates the scene's codebase, and reports the first divergence
with the mis-modeled instruction and +/-3 ops of context on each side (opcode
+ rendered line via sys4load).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
