feat(throwing): core gargoyle Throwing skill (SA) (#2510)

Supersedes #2376 (@jwvalentine). This is a reviewed, corrected, and scoped-down **Phase 1** of Joe Valentine's throwing implementation — his original commits are cherry-picked here with authorship preserved, plus a fix/scoping pass. Phase 1 lands only the **core gargoyle Throwing skill**; the incomplete content is excised for follow-up PRs (see below).

## What's included (core skill)
- `BaseThrown` combat mechanics on top of the existing skeleton: close-quarters penalty, below-min-range penalty, shield penalty, STR-scaled range, overthrow damage penalty.
- Base weapons: **Boomerang, Cyclone, SoulGlaive** (gargoyle-only), + blacksmith crafting (SA-gated).
- Two symmetric hooks on `BaseWeapon` (`ModifyHitChance`, new `ModifyDamage`) that are inert no-ops for every other weapon.

## Fixes over the original
- **Overthrow damage**: was dead code (the swing gate already guarantees you're within `MaxRange`, so the old `ComputeDamage` check never fired). Reimplemented as `finalDamage × 0.53` applied *after* all offensive bonuses via a new `ModifyDamage` hook, firing at the outer range ring.
- **`DefMaxRange`**: clamped to `[MinThrowRange, MaxThrowRange]` (uncapped before → e.g. range 13 at 200 Str) and guarded against a latent divide-by-zero.
- **Close-quarters mitigation** now uses `RawDex` (matches ServUO/OSI; deterministic under stat mods).
- **Return-throw timer** guarded against a deleted/unmapped thrower/target.
- Reverted the `MovingShot` change (it rebalanced archery — belongs in a separate PR).
- Kept only complex-logic tests (hit-chance/range/damage math); dropped property-value assertions.

## Excised for follow-up PRs (Phase 2/3)
7 named artifacts, the Into-the-Void quest + Agralem, GargishOutcast, the Bladeweaver vendor, and the SA loot tables — these were unwired/non-functional (loot never triggered, quest/creature never spawned) and will return properly wired. `StormCaller` also needs its missing Battle Lust, and the quest its correct void-creature target.

## Verification
- Build: 0 warnings / 0 errors.
- `UOContent.Tests`: **501/501** passing (the `ModifyDamage` hook causes zero regressions across all weapons).
- Full whole-branch review completed: no must-fix defects.

Projects/UOContent/Engines/Craft/DefBlacksmithy.cs

@@ -667,6 +667,18 @@ public class DefBlacksmithy : CraftSystem
         index = AddCraft(typeof(DragonChest), 1053114, 1029793, 85.0, 135.0, typeof(RedScales), 1060883, 36, 1060884);
         SetUseSubRes2(index, true);
 
+        if (Core.SA)
+        {
+            index = AddCraft(typeof(Boomerang), 1079508, 1095359, 75.0, 125.0, typeof(IronIngot), 1044036, 5, 1044037);
+            SetNeededExpansion(index, Expansion.SA);
+
+            index = AddCraft(typeof(Cyclone), 1079508, 1095364, 75.0, 125.0, typeof(IronIngot), 1044036, 9, 1044037);
+            SetNeededExpansion(index, Expansion.SA);
+
+            index = AddCraft(typeof(SoulGlaive), 1079508, 1095363, 75.0, 125.0, typeof(IronIngot), 1044036, 9, 1044037);
+            SetNeededExpansion(index, Expansion.SA);
+        }
+
         // Set the overridable material
         SetSubRes(typeof(IronIngot), 1044022);