Add accounts, presets, live sheet panel and equipment tiles

- Login with registration code, sessions, rate limiting, per-user characters
- Share characters with other users (read-only), admin CLI
- Rules presets with a Presets tab, applied/pending changes with diff in a side sheet
- Equipment as tiles with amounts, starting kit removed
- Rename nav tab to "Character", add "New character" button
- Stop tracking _to_delete/

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

frontend/src/sheetModel.js

@@ -8,7 +8,7 @@ export function sheetModel(ch, baseRules) {
   const cls = rules.classes.find((k) => k.id === ch.class_id)
   const sub = cls?.subclasses.find((x) => x.id === ch.subclass_id)
   const preset = ch.preset === 'custom' ? 'Custom' : baseRules.presets?.find((p) => p.id === ch.preset)?.name || 'Custom'
-  const training = (s) => (s.pips === 2 ? 'Expertise' : s.pips === 1 ? 'Proficient' : s.type === 'advanced' && s.unlocked ? 'Unlocked' : '')
+  const training = (s) => (s.pips === 2 ? 'Expertise' : s.pips === 1 ? 'Proficient' : !s.usable ? 'Locked' : s.type === 'advanced' ? 'Unlocked' : '')
   return {
     c,
     head: [
@@ -19,8 +19,7 @@ export function sheetModel(ch, baseRules) {
     ],
     attrs: rules.attributes.map((a) => ({ k: a.id, label: a.name, val: c.attrs[a.id], extra: `Mod ${c.mods[a.id]}` })),
     derived: rules.derived.map((d) => ({ k: d.id, label: d.name, val: c.derived[d.id] })),
-    skills: c.skills.filter((s) => s.points || s.prof || (s.unlocked && s.type === 'advanced'))
-      .map((s) => ({ k: s.id, label: s.name, val: s.total, extra: training(s) })),
+    skills: c.skills.map((s) => ({ k: s.id, label: s.name, val: s.total, extra: training(s), dim: !s.usable })),
     talents: rules.talents.filter((t) => ch.talents.includes(t.id)).map((t) => ({ k: t.id, label: t.name, desc: t.desc })),
     augments: rules.augments.filter((a) => ch.augments.includes(a.id)).map((a) => ({ k: a.id, label: a.name, desc: `${a.kind === 'implant' ? 'Implant' : 'Mutation'} · cost ${a.cost}${a.desc ? ` · ${a.desc}` : ''}` })),
     gear: kitItems(ch, rules).map((g) => ({ k: g.item.id, label: g.item.name, val: g.qty, desc: [g.item.stat, `${g.item.kg} kg`, g.item.note].filter(Boolean).join(' · ') })),