Implement d6 wild dice/fumble skills and die-state rolls

REQUIREMENTS.md

@@ -98,6 +98,8 @@
 
   * name
   * diceRollDefinition (ruleset-compliant expression, e.g. `5D+4`, `2d12+2`)
+  * wildDice (d6 only; number of wild dice)
+  * allowFumble (d6 only; whether wild-1 fumbles remove dice)
 * Behavior:
 
   * Can be rolled
@@ -198,6 +200,7 @@
 * System must:
 
   * Validate dice expressions against the campaign ruleset
+  * Validate d6 skill options (`wildDice`, `allowFumble`) as part of skill create/edit
 
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@@ -213,7 +216,9 @@
 * System must:
 
   * Evaluate dice expressions deterministically and fairly
+  * For d6 skills, apply wild-die explosions and fumble-removal logic
   * Record all rolls in the campaign log
+  * Return die-by-die roll states so the frontend can visualize critical/fumble/wild/removed/added outcomes
 
 ---
 
@@ -263,6 +268,7 @@
 ### Skills
 
 * As a **player**, I want to define skills with dice formulas so that I can perform actions.
+* As a **player**, I want to configure wild dice and fumble behavior for d6 skills so the roll follows my table rules.
 * As a **GM**, I want to edit character skills so that I can enforce or adjust rules.
 
 ---
@@ -270,6 +276,7 @@
 ### Dice Rolling
 
 * As a **player**, I want to roll dice for a skill so that I can resolve actions.
+* As a **player**, I want to see which dice were wild, exploded, fumbled, removed, or added so that I can audit the roll result.
 * As a **user**, I want to choose whether a roll is public or private so that I can control information visibility.
 * As a **GM**, I want to see all rolls (including private ones) so that I can oversee the game.