[Tracker]: Engine accuracy improvements (audit warnings W1-W9)

[Xerrion]

Summary

Tracker for nine WARNING-severity findings from the engine accuracy audit. Each is independently fixable; this issue serves as the umbrella for sub-PRs. Some are quick wins (W1, W2, W7), others require encoding audits (W3, W4) or design decisions (W5, W6, W9). W8 is deferred per #44.

Findings

W1 - Hunter ranged base crit multiplier 1.5x instead of 2.0x

Location: Engine/CritCalc.lua:102-108
Issue: BASE_CRIT_MULTIPLIER (1.5x spell crit) is applied for scalingType="ranged" spells. Per Wowwiki Critical_strike, ranged crits use the 2.0x melee multiplier in TBC.
Impact: ~11% understatement at 25% crit chance for Hunter spells (Arcane Shot, Multi-Shot, Aimed Shot, Steady Shot, Volley, Serpent Sting tick crits).
Fix: Branch on isMelee or isRanged to use 2.0x base, or add BASE_RANGED_CRIT_MULTIPLIER = 2.0 constant.

W2 - Rogue/Cat-form GCD floor 1.5s instead of 1.0s

Location: Engine/CritCalc.lua:42-56, Core/Constants.lua:85
Issue: GLOBAL_COOLDOWN = 1.5 applied uniformly. Energy-based abilities (Rogue, Cat-form Druid) have a 1.0s GCD in TBC.
Impact: Up to 33% DPS understatement on Sinister Strike, Backstab, Eviscerate, Shred, Mangle (Cat), Claw, Rake.
Fix: Per-spell gcd field in SpellData, or derive from playerState.class + spell category.

W3 - CRIT_MULT_BONUS data convention unverified

Location: Engine/CritCalc.lua:108, all Data/TalentMap_*.lua
Issue: critMultBonus is added to baseCritMult. Talents like Ruin (Warlock, "+100% crit damage" → 2.0x crits) require encoding the delta (value = 0.5), not the full multiplier.
Affected talents: Ruin, Ice Shards 5/5, Spell Power 5/5 (0.1), Vengeance 5/5 (0.5), Shadow Power 5/5 (0.5), Mortal Shots 5/5 (0.3), Lethality 5/5 (0.3).
Impact: If TalentMap encoded the full multiplier, math is off by 50-100%.
Fix: Spot-check audit of each TalentMap entry; document convention in code comments.

W4 - Heal-flagged spells use spell damage instead of healing power

Location: Engine/SpellCalc.lua:70,244,276,331,363, StateCollector.lua:196-199
Issue: state.stats.healingPower = GetSpellBonusHealing() is collected but unused. All Compute* paths read playerState.stats.spellPower[school] regardless of isHeal flag.
Impact: Currently affects only Paladin Holy Shock heal variant (synthetic ID 200473, isHeal=true). Latent for future heal additions.
Fix: Branch on spellData.isHeal in each Compute* and in ModifierCalc.BuildModifiedResult:347-354 to read healingPower instead.

W5 - Curse of Agony ramping flagged but not modeled

Location: Data/SpellData_Warlock.lua:211-233 isRamping=true
Issue: Flag exists with no consumer. CoA delivers 50%/100%/150% per third of duration. Total damage is correct (sum stored). Per-tick UI display would be uniform (wrong if any consumer reads tickDamage per-tier).
Impact: Averaged-EV math correct; fidelity gap only.
Fix: Either remove flag with explanatory comment, or compute per-third tick distributions in BuildPeriodicResult.

W6 - Hybrid coefficientBonus only applies to direct portion

Location: Engine/ModifierCalc.lua:455-462
Issue: Empowered Fireball (direct-only DoT scaling) is correctly handled. Future hybrid talents whose DoT also scales would silently break.
Fix: Add MOD.DOT_COEFFICIENT_BONUS modifier type for symmetry, or appliesToDot filter on hybrid coefficient bonuses.

W7 - expertiseReduction magic number 0.0025 instead of EXPERTISE_PER_PERCENT=4.0

Location: Engine/CritCalc.lua:122, Constants.lua:72
Issue: Hardcoded 0.0025 instead of using existing constant.
Fix: expertiseReduction = expertise / (EXPERTISE_PER_PERCENT * 100). Pure refactor.

W8 - Partial resist (~6% systematic loss) unmodeled - DEFERRED

Location: Engine/CritCalc.lua:189,241,313
Status: Out of scope per #44 deferral. Logged for catalog completeness.
Future fix: Multiply expectedWithMiss * (1 - 0.06) for boss-level same-school targets when target-level signal is available.

W9 - damageBeforeMods field semantics inconsistent

Location: Engine/ModifierCalc.lua:476
Issue: Direct/DoT/channel paths set damageBeforeMods pre-multiplier; hybrid path sets it to baseResult.totalDamage (post-SP).
Impact: Diagnostics consumers expecting consistent semantics may misrender hybrid spells.
Fix: Standardize across all three paths to mean "post-SP, post-flat, pre-multiplier".

Sequencing recommendation

1. Quick wins first (W1, W2, W7) - small, isolated, high signal.
2. Encoding audit (W3) - audit + fix TalentMap entries; may reveal cascading corrections.
3. Healing path (W4) - enables future Paladin/Druid heal work.
4. Polish (W5, W6, W9) - fidelity and consistency.
5. W8 stays deferred until [Bug]: Expected damage overestimates actual; add diagnostic for missing-overlay spells #44 resolves.

Dependencies

• W1, W2, W3 are touched by the BLOCKER fixes for downranking penalty (separate issue) only insofar as both modify CritCalc.lua and SpellData_*.lua. Sequence: BLOCKERs first, then warnings.