- Inferno (Offense, seat 2): flame arcs home on the nearest 2 hostiles
(3 from rank 4) and ignite a burn that ticks on the combat loop's clock;
scales in duration and per-tick damage with rank.
- Nanobots (Passive, no seat): mends 1% of max hull every 2s per point;
a full hull banks nothing.
- Wire flameArc + hullRegen effect handlers in SkillEffects.js and the
arc/burn/step logic in CombatSystem.js.
- Add firstPassiveOf() / hullRegen() to the skill ledger so the combat
loop can read the mend's interval and color off the ranked def.
- Update icon sheet, dev shots, and the browser/combat/data test suites for
the two new skills.
