H02 StampTreatyTurns -- the diplomacy ledger's "this treaty was last in force on turn
N" stamp, over every ordered pair of players that holds one, creating the entry on
demand. It is a host step, not a phase of either turn driver: its sole caller is the
command-application step, which runs after the frame counter has advanced and before
both drivers. On a turn with no combat and no diplomatic command it is the only writer
of these fields, which is why a whole per-player dipstats vector is its output.
Read from the instruction stream; three things an earlier reading had wrong are
corrected in findings/subsystems/treaty-turn-stamp.md: the stamped value is the TURN and
not the modification counter, the relation codes are 3=allied / 2=NAP / 1=cease-fire and
not the reverse, and the bit is the player's index field rather than its position in the
player vector -- the opposite convention from the shared-vision mask two files away.
Measured, closed and regressed reported separately and never netted:
turn1 -> turn2 (reference) 209 -> 132 closed 77 (was 51), regressed 0
turn2 -> turn3 108 -> 73 closed 35 (was 21), regressed 0
human-turn2 -> turn3 closed 76 (was 64), regressed 0
zuul-turn15 -> turn16 closed 30 (was 18), regressed 0
zuul-turn16 -> turn17 closed 29 (was 17), regressed 0
The last three are pairs from a different game at turns 2, 15 and 16 that the model was
never fitted to, and it closes exactly the twelve ordered treaty pairs each of them holds.
The rule also reproduces the ledger of ten of the eleven corpus saves entry for entry,
including each entry's order and every stamped value; the eleventh is the turn-1 save
whose ledger no turn has yet written, and it is the reference pair's input.
app_test_treaty pins the five things the corpus cannot separate: the relation codes (no
save exercises cease-fire), the bit's source, the missing alliance-id guard, the -1
initialiser on a fresh entry, and the append-at-the-end order that makes re-running the
step idempotent instead of duplicating rows.
The betrayal half of the same function needs the turn's diplomatic commands; with no
command stream it is provably a no-op and is not modelled.
