Pre-HardStop Timing Alignment priority slot static design

Scope:
- No implementation was performed.
- This is a static design comparison using existing lifecycle/snapshot fields only.
- HardStopPriority-time back-calculation is diagnostic only and not used in conditions.

Option 1: Evaluate TA9 before existing HTE
- HardStop rescue: 26 baskets.
- HTE Kill risk: 1 basket / 70.00 yen.
- Existing close conflict: highest, because a TA9 POST_HEDGE_SLOT exit can preempt a later HTE success.
- priority_order_change_required: true.
- implementation complexity: high.
- fail-safe: requires explicit HardStopNow=false and ClosePriorityOK=true snapshot gate.
- unknown risk: same-tick HardStop/HTE sequencing and market-closed retry behavior.

Option 2: Evaluate TA9 after existing HTE, before HardStop
- HardStop rescue: may be close to TA9 if HTE is not currently eligible; exact effect needs runtime HTE eligibility snapshot.
- HTE Kill risk: lower than Option 1 if current HTE eligibility is checked before TA9.
- Existing close conflict: medium; HTE timing and acceptable-loss checks must be shared, not duplicated.
- priority_order_change_required: true.
- implementation complexity: high.
- fail-safe: safer than Option 1 but needs additional HTE eligibility trace at the same eval_stage.
- unknown risk: if HTE is not yet eligible but will be eligible minutes later, TA9 can still kill future HTE.

Option 3: POST_HEDGE_SLOT with HTE-near fallback to TA5 / distance safety
- HardStop rescue: TA9 original 26 baskets; TA5 baseline 20 baskets.
- HTE Kill risk: can be reduced to 0 with the best real-time filter found here: TA9_FILTER_DISTANCE_TO_HARDSTOP_NONNEG (distance_to_hardstop_yen >= 0).
- Filtered net effect: 32830.00 yen.
- Existing close conflict: medium; HTE/recovery/basketclose guard logs are mandatory.
- priority_order_change_required: true.
- implementation complexity: medium-high.
- fail-safe: best of the aggressive options if distance_to_hardstop_yen sign and HTE state are logged at runtime.
- unknown risk: distance_to_hardstop_yen < 0 while ClosePriorityOK=true is a same-tick edge and must be parity-logged before P1.

Option 4: Reject TA9 and evaluate TA5 only
- HardStop rescue: 20 baskets.
- HTE Kill risk: 0 / Recovery Kill 0 / BasketClose Kill 0.
- Net effect: 20063.00 yen versus TA9 original 32760.00 yen and TA4 14003.00 yen.
- Existing close conflict: lower than TA9, but still requires POST_HEDGE_SLOT and priority-order change.
- priority_order_change_required: true.
- implementation complexity: medium.
- fail-safe: highest among the non-zero candidates.
- unknown risk: effect is weaker and biased toward 50k logs.

Design conclusion:
- TA9 raw is not directly P1-ready because it kills one HTE success basket.
- TA9 can likely be made safer using a real-time field, distance_to_hardstop_yen >= 0, without losing observed HardStop rescues in the current six logs.
- Because this still requires POST_HEDGE_SLOT / priority-order change, the decision class remains TA9_DESIGN_REQUIRED, not immediate P1 implementation.
- If a simpler next P1 is required without resolving TA9 slot details, TA5 is the safer fallback.
