Support Cadiro's Gambit's Perandus Arrows

[lucaskarsten]

Related to #2415.

Description of the problem being solved:

Cadiro's Gambit has the line "Each Arrow fired is a Crescendo, Splinter, Reversing, Diamond, Covetous, or Blunt Arrow", which was unsupported, so the quiver calculated as if it only granted increased Attack Speed.

The Diamond Arrow is what makes that matter: all its Hits are Critical Hits, with 60% increased Critical Damage Bonus. On a bow character sitting at 28.88% Critical Hit Chance, that Arrow takes Total DPS from 120,714 to 297,952.

The six Arrows are rolled per Arrow and behave too differently to average into one number, so the item's line only sets a flag and a new config picks which Arrow to calculate. This follows the existing "Random element mode" config for modifiers that choose an element. The default, "Random (none applied)", applies none of them, so no existing build changes.

Each Arrow reuses modifiers that already exist:

Arrow	Modifiers
Crescendo	ChainCountMax +6, 60% increased Damage per Chain
Splinter	SplitCount 6
Reversing	PierceAllTargets
Diamond	CritChance 100 override, 60% increased CritMultiplier
Covetous	600% increased LootRarity
Blunt	600% increased EnemyHeavyStunBuildup

The Reversing Arrow also returns to you, which PoB does not model.

Steps taken to verify a working solution:

• Equipped Cadiro's Gambit on a level 96 Ice Shot Deadeye and stepped through every option of the new config.
• Diamond: Total DPS 120,714 -> 297,952, Crit Chance 28.88% -> 100.00%, Crit Multiplier 396% -> 456%. Screenshots below.
• Crescendo: Chain Max 0 -> 6, and with "# of times Skill has Chained" set to 6, Full DPS 392,738 -> 651,538.
• Splinter: Split Count 0 -> 6. Reversing: Pierce Count 0 -> "All targets". Neither changes single target DPS, as expected.
• Regenerated ModCache.lua, which now caches the line as a parsed flag instead of an unsupported mod.

Link to a build that showcases this PR:

Any bow build with this item works. The quiver used above:

Rarity: UNIQUE
Cadiro's Gambit
Primed Quiver
Item Level: 82
LevelReq: 66
Implicits: 0
10% increased Attack Speed
Each Arrow fired is a Crescendo, Splinter, Reversing, Diamond, Covetous, or Blunt Arrow

Before screenshot:

After screenshot:

[lucaskarsten]

Pushed a fix: the config now gates itself on Condition:PerandusArrows, granted by the quiver.

ifFlag only decides whether the control is drawn (ConfigTab.lua:445), while ConfigTab:BuildModList applies every stored list var regardless (ConfigTab.lua:902). Without the condition, a build that picked Diamond and then unequipped the quiver kept CritChance OVERRIDE 100 with the control no longer visible — measured 100% Critical Hit Chance on a character with no Cadiro's Gambit equipped. Every other item-gated ifFlag option in the file only sets a Condition: or Multiplier: that is inert without its item, so this was the odd one out.

With the quiver equipped the numbers are unchanged (Diamond still 903,906 Full DPS on the character in the description); without it, the character measures its normal 29.45% Critical Hit Chance again.

ModCache.lua regenerated with REGENERATE_MOD_CACHE=1 luajit HeadlessWrapper.lua. Full busted suite: 566 successes / 0 failures / 0 errors.