feat: add Settlement actor type with Overview/Buildings/Inventory tabs

- New TypeDataModel: archetype, territory, renown, currency (gp/sp/cp),
  garrison, underSiege, isCapital, founded, taxNotes, description, notes
- 3-tab ApplicationV2 sheet with drag & drop for building/weapon/armor/equipment
- Currency steppers (+/−), building constructed toggle, qty controls
- LESS-based CSS (settlement-sheet.less) + base.less updated for shared styles
- Full i18n keys in lang/en.json (8 settlement archetypes)
- system.json: registered settlement actor type

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

module/models/character.mjs

@@ -78,8 +78,9 @@ export default class OathHammerCharacter extends foundry.abstract.TypeDataModel
     })
 
     schema.arcaneStress = new fields.SchemaField({
-      value: new fields.NumberField({ ...requiredInteger, initial: 0, min: 0 }),
-      threshold: new fields.NumberField({ ...requiredInteger, initial: 10, min: 0 })
+      value:         new fields.NumberField({ ...requiredInteger, initial: 0, min: 0 }),
+      threshold:     new fields.NumberField({ ...requiredInteger, initial: 0, min: 0 }),
+      thresholdBonus: new fields.NumberField({ ...requiredInteger, initial: 0, min: 0 })
     })
 
     schema.miracleBlocked = new fields.BooleanField({ required: true, initial: false })
@@ -130,5 +131,7 @@ export default class OathHammerCharacter extends foundry.abstract.TypeDataModel
     this.luck.max = this.attributes.fate.rank
     // Defense score = 10 + Agility + Armor Rating + bonus
     this.defense.value = 10 + this.attributes.agility.rank + this.defense.armorRating + this.defense.bonus
+    // Stress Threshold = Willpower rank + Magic rank + bonus (rulebook p.101)
+    this.arcaneStress.threshold = this.attributes.willpower.rank + this.skills.magic.rank + this.arcaneStress.thresholdBonus
   }
 }