feat(ui): Velocity rollout — page polish + lime-as-text contrast fixes

Roll the re-skin across the remaining surfaces and fix the readability
regressions the lime accent introduced (lime works as a fill/border but is
unreadable as text on light):

- --m-c-rule is now a soft divider, so page panels/tables get tidy outlines
  instead of a mess of black hairlines; the brutalist weight stays on cards,
  nav, sections and inputs (which reference ink directly).
- New --m-c-warning (amber) for medium severity, keeping the low→medium→high
  gradient legible; applied to SeverityBadge, AnomalyCard, feed stat.
- Interactive/link/highlight text (Home CTA + links, Journal/Backtest/Compare
  buttons, KPI + evidence values) moved off lime to the readable --m-c-info
  blue; Home first-run CTA is now a filled-lime brutalist button; odds-up
  delta → positive green; rate arrow → neutral.
- Results winner colours → tokens (positive / info) + Velocity-aligned tints.

CSS-only — build clean, all 568 tests green.

src/Marathon.UI/Pages/Results/ResultsLoader.razor

@@ -198,8 +198,8 @@
         border-radius: var(--m-radius-xs);
         border: 1px solid var(--m-c-rule);
     }
-    .m-result-winner--side1 { background: rgba(34,197,94,0.10); color: #15803d; border-color: rgba(34,197,94,0.30); }
-    .m-result-winner--side2 { background: rgba(59,130,246,0.10); color: #1d4ed8; border-color: rgba(59,130,246,0.30); }
+    .m-result-winner--side1 { background: rgba(31,158,61,0.10); color: var(--m-c-positive); border-color: rgba(31,158,61,0.32); }
+    .m-result-winner--side2 { background: rgba(36,75,255,0.10); color: var(--m-c-info); border-color: rgba(36,75,255,0.32); }
     .m-result-winner--draw  { background: rgba(120,113,108,0.10); color: var(--m-c-ink-soft); }
 </style>