Skills: +-5 buttons, advanced skills use 50% of the attribute (creation.advanced_attr_percent)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HJhXuLD2Z6hv3Wqeq9UL9K

frontend/src/Creator.jsx

@@ -314,9 +314,11 @@ export default function Creator({ rules: baseRules, user, loadRequest, clearLoad
                         <button className="ghost small-btn" title={`Lock again: you get ${c.unlockCost} points back, its points and proficiency picks are returned`}
                           onClick={() => setCh((x) => ({ ...x, unlocked: x.unlocked.filter((id) => id !== s.id), skill_points: { ...x.skill_points, [s.id]: 0 }, proficiency_picks: { ...x.proficiency_picks, [s.id]: 0 } }))}>Lock</button>
                       )}
-                      <button onClick={() => setPts(s.points - 1)} aria-label={`${s.name} minus`}>−</button>
+                      <button className="step5" onClick={() => setPts(s.points - 5)} disabled={s.points <= 0} aria-label={`${s.name} minus 5`}>−5</button>
+                      <button onClick={() => setPts(s.points - 1)} disabled={s.points <= 0} aria-label={`${s.name} minus`}>−</button>
                       <span className="val">{s.points}</span>
-                      <button onClick={() => setPts(s.points + 1)} disabled={s.points >= s.max || c.skillLeft <= 0} aria-label={`${s.name} plus`}>+</button>
+                      <button onClick={() => setPts(Math.min(s.points + 1, s.max, s.points + c.skillLeft))} disabled={s.points >= s.max || c.skillLeft <= 0} aria-label={`${s.name} plus`}>+</button>
+                      <button className="step5" onClick={() => setPts(Math.min(s.points + 5, s.max, s.points + c.skillLeft))} disabled={s.points >= s.max || c.skillLeft <= 0} aria-label={`${s.name} plus 5`}>+5</button>
                       <Tip text={explainSkill(s, ctx)}><span className="mod">{s.total}</span></Tip><span className="small muted" title="Most points you can add"> max {s.max}</span>
                     </div>
                   )}