Implement the P.ATTACK / G.ATTACK gauge types (LR2)

Context

Found by reverse-engineering the actual LR2 (LR2body.exe, beta3) shipped files. LR2's gauge list is larger than what we model.

First-party evidence

• LR2files/Config/optionstr.csv: #GAUGE,GROOVE,SURVIVAL,DEATH,EASY,P.ATTACK,G.ATTACK — LR2 offers six gauges.
• history.txt (080313): "ゲージオプションに、PERFECT ATTACKとGOOD ATTACKを追加しました。… PAはGOOD以下で閉店し、黄GREATで少量ゲージが減少します。GAは黄GREATで少量、光GREATでPOORと同量ゲージが減少します。クリアはハードクリア扱いとなります。"
  • P.ATTACK: fails (closes) on GOOD-or-worse; a non-PGREAT GREAT drains a small amount.
  • G.ATTACK: a non-PGREAT GREAT drains a small amount, a PGREAT-flagged GREAT drains the same as a POOR. Clear counts as a HARD clear.

Naming note

Our GrooveGaugeType uses HARD / DEATH; LR2 calls these SURVIVAL / DEATH. Worth aligning the labels (or at least documenting the mapping) when adding the new types.

Current behavior

packages/player/src/core/groove-gauge.ts models GROOVE / HARD (= LR2 SURVIVAL) / DEATH / EASY only. P.ATTACK and G.ATTACK are absent.

Notes

• The engine currently only exercises GROOVE (gauge-type selection isn't user-exposed yet), so this is gated on gauge-type selection landing first.
• The binary's gauge constant pool (.rdata ~0x744830) contains unmodeled values (0.048, 0.12, -3.0, ...) that likely belong to these gauges; map them via xref when implementing.

Start with packages/player/src/core/groove-gauge.ts and confirm how the existing GROOVE, HARD, DEATH, and EASY types update and clear. Use the LR2 evidence in LR2files/Config/optionstr.csv and history.txt, then trace references to the binary gauge constants near .rdata ~0x744830. Done means P.ATTACK and G.ATTACK are modeled with the documented drain, failure, and HARD-clear behavior, with the HARD/SURVIVAL naming mapping addressed.