D0 Part 2: design system v2 — tokens, meter/tag/metarow, funcmap remap, dashboard + stacks

- style.css: navy token palette (--bg-0/1/2, --line, --text-1/2/3, --blue,
  --warn, --crit), single 2px radius, all box-shadows and the bg grid
  overlay removed, fonts via --font-ui/--font-data.
- Components: .meter (3px hairline track, blue nominal fill, neutral
  70/85 ticks, warn/crit flag), .tag (square 2px state chip + dot, pulse
  on progress, reduced-motion respected), .metarow (icon + text, no
  container), .panel/.list/.section-h primitives, boxless .stats with
  hairline dividers, buttons 2px (danger = crit outline).
- funcmap: stateColor -> run/progress/warn/neutral/off (stopped is
  neutral, NOT red — operator-approved exception-color change),
  usageColor/tempColor -> nominal/warn/crit (thresholds unchanged);
  stateLabel Hungarian copy untouched (guarded by test).
- layout.html: sprite nav icons (layout-grid/cloud/shield/cpu/wrench/
  settings), alert banner emoji -> triangle-alert/info icons.
- dashboard.html: meters with disk warn/crit flags (Fogyóban a hely /
  Kritikusan kevés hely), boxless stats (Leállítva 0 muted, >0 amber),
  single-panel stack list with 2px state edges, tags instead of badges,
  icon action buttons.
- stacks.html: state tag + metarow rows; catalog keeps its grid.
- setup minimalCSS retokened to v2 (drops GitHub-dark hexes).
- Tests: §8 truth tables for stateColor/usageColor/tempColor +
  stateLabel byte-identity guard (red-proven vs pre-change funcmap:
  stopped->red and 0->green failed as required).

controller/internal/web/templates/layout.html

@@ -21,14 +21,14 @@
             <span class="customer-name">{{.CustomerName}}</span>
         </div>
         <ul class="nav-links">
-            <li><a href="/" class="{{if eq .Page "dashboard"}}active{{end}}">Vezérlőpult</a></li>
-            <li><a href="/stacks" class="{{if eq .Page "stacks"}}active{{end}}">Alkalmazások</a></li>
-            <li><a href="/backups" class="{{if eq .Page "backups"}}active{{end}}">Biztonsági mentés</a></li>
-            <li><a href="/monitoring" class="{{if eq .Page "monitoring"}}active{{end}}">Rendszermonitor</a></li>
-            {{if .DebugMode}}<li><a href="/debug" class="{{if eq .Page "debug"}}active{{end}}">🔧 Debug</a></li>{{end}}
+            <li><a href="/" class="{{if eq .Page "dashboard"}}active{{end}}"><svg class="ico"><use href="#i-layout-grid"/></svg>Vezérlőpult</a></li>
+            <li><a href="/stacks" class="{{if eq .Page "stacks"}}active{{end}}"><svg class="ico"><use href="#i-cloud"/></svg>Alkalmazások</a></li>
+            <li><a href="/backups" class="{{if eq .Page "backups"}}active{{end}}"><svg class="ico"><use href="#i-shield"/></svg>Biztonsági mentés</a></li>
+            <li><a href="/monitoring" class="{{if eq .Page "monitoring"}}active{{end}}"><svg class="ico"><use href="#i-cpu"/></svg>Rendszermonitor</a></li>
+            {{if .DebugMode}}<li><a href="/debug" class="{{if eq .Page "debug"}}active{{end}}"><svg class="ico"><use href="#i-wrench"/></svg>Debug</a></li>{{end}}
         </ul>
         <div class="sidebar-bottom">
-            <a href="/settings" class="sidebar-settings-link {{if eq .Page "settings"}}active{{end}}">⚙ Beállítások</a>
+            <a href="/settings" class="sidebar-settings-link {{if eq .Page "settings"}}active{{end}}"><svg class="ico"><use href="#i-settings"/></svg>Beállítások</a>
             <div class="sidebar-footer">
                 <span class="version">{{.Version}}</span>
                 {{if .AuthEnabled}}<a href="/logout" class="logout-link">Kijelentkezés ↗</a>{{end}}
@@ -41,7 +41,7 @@
     {{range .Alerts}}
     {{if and (not .Inline) (or (not .PageOnly) (pageMatch .PageOnly $.Page))}}
     <div class="alert-banner alert-banner-{{.Level}}">
-        <span class="alert-icon">{{if eq .Level "error"}}🔴{{else if eq .Level "warning"}}🟡{{else}}ℹ️{{end}}</span>
+        <span class="alert-icon"><svg class="ico">{{if eq .Level "error"}}<use href="#i-triangle-alert"/>{{else if eq .Level "warning"}}<use href="#i-triangle-alert"/>{{else}}<use href="#i-info"/>{{end}}</svg></span>
         <span class="alert-message">{{.Message}}</span>
         {{if .Link}}<a href="{{.Link}}" class="alert-link">{{.LinkText}} →</a>{{end}}
     </div>