fix(icons): inject missing sprite symbols for newly added icons

The icon sprite was injected once and never updated, so HMR/new glyphs
like telegram-fill left <use> refs empty. Append missing symbols on render.

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>

packages/ui/src/components/icon/Icon.tsx

@@ -30,6 +30,29 @@ function ensureSpriteOnce() {
   spriteInjected = true
 }
 
+/**
+ * Append a single missing symbol. Needed when the sprite was injected before a
+ * newly generated icon landed (HMR / late sprite regenerate) — a one-shot inject
+ * would otherwise leave `<use href="#oc-…"/>` pointing at nothing.
+ */
+function ensureSpriteSymbol(name: IconName) {
+  if (typeof document === "undefined") return
+  ensureSpriteOnce()
+  if (document.getElementById(`oc-${name}`)) return
+
+  const content = iconSpriteData[name]
+  if (typeof content !== "string") return
+
+  const sprite = document.getElementById(SPRITE_ID)
+  if (!sprite) return
+
+  const symbol = document.createElementNS("http://www.w3.org/2000/svg", "symbol")
+  symbol.id = `oc-${name}`
+  symbol.setAttribute("viewBox", "0 0 24 24")
+  symbol.innerHTML = content
+  sprite.appendChild(symbol)
+}
+
 export interface IconProps extends React.ComponentPropsWithoutRef<"svg"> {
   name: IconName
 }
@@ -38,7 +61,7 @@ export const Icon = React.memo(({ name, className, ...rest }: IconProps) => {
   // Inline sprite injection during render – must run before <use> tries
   // to resolve the #oc-* reference during the same commit.
   if (typeof document !== "undefined") {
-    ensureSpriteOnce()
+    ensureSpriteSymbol(name)
   }
 
   return (