Use the brand loading mark instead of lucide's spinner

Copies index/frontend's FluksioLoader component and its
`.fluksio-loader-line` rule into the app (the shadcn duplication model, so
the CSS travels with the component) and swaps every Loader2 pending state
over: the router's pending screen, the flow dock's Run and Publish, the
dashboard editor's Publish, the overview toolbar's Publish-all and
LoadingButton. One loading mark across both shells.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K1moruzue2kTJd3uVisgNk

frontend/src/components/Common/Loading.tsx

@@ -1,4 +1,4 @@
-import { Loader2 } from "lucide-react"
+import { FluksioLoader } from "@/components/ui/fluksio-loader"
 
 /**
  * The router's pending screen, shown while a page's code chunk is on its way.
@@ -15,7 +15,7 @@ export function PageLoading() {
       data-testid="page-loading"
       className="flex min-h-64 items-center justify-center"
     >
-      <Loader2 className="size-6 animate-spin text-muted-foreground" />
+      <FluksioLoader className="size-6 text-muted-foreground" />
     </output>
   )
 }

frontend/src/components/Common/OverviewToolbar.tsx

@@ -1,5 +1,5 @@
 import { useMutation } from "@tanstack/react-query"
-import { Check, Loader2, Plus, Search, Trash2 } from "lucide-react"
+import { Check, Plus, Search, Trash2 } from "lucide-react"
 import { motion } from "motion/react"
 import { type ReactNode, useRef, useState } from "react"
 
@@ -13,6 +13,7 @@ import {
   DialogTitle,
   DialogTrigger,
 } from "@/components/ui/dialog"
+import { FluksioLoader } from "@/components/ui/fluksio-loader"
 import { Input } from "@/components/ui/input"
 import {
   Tooltip,
@@ -170,7 +171,7 @@ export function OverviewToolbar({
               aria-label="Publish all changes"
               data-testid="publish-all"
             >
-              {publishing ? <Loader2 className="animate-spin" /> : <Check />}
+              {publishing ? <FluksioLoader /> : <Check />}
             </Button>
           </span>
         </TooltipTrigger>

frontend/src/components/Dashboard/DashboardEditor.tsx

@@ -1,14 +1,6 @@
 import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query"
 import { useNavigate } from "@tanstack/react-router"
-import {
-  Check,
-  ExternalLink,
-  Loader2,
-  Pencil,
-  Plus,
-  Settings2,
-  X,
-} from "lucide-react"
+import { Check, ExternalLink, Pencil, Plus, Settings2, X } from "lucide-react"
 import { motion } from "motion/react"
 import { type CSSProperties, useEffect, useRef, useState } from "react"
 import {
@@ -36,6 +28,7 @@ import {
   DialogHeader,
   DialogTitle,
 } from "@/components/ui/dialog"
+import { FluksioLoader } from "@/components/ui/fluksio-loader"
 import {
   Popover,
   PopoverContent,
@@ -720,7 +713,7 @@ export function DashboardEditor({
                       data-testid="publish-dashboard"
                     >
                       {save.isPending || publish.isPending ? (
-                        <Loader2 className="size-3.5 animate-spin" />
+                        <FluksioLoader className="size-3.5" />
                       ) : (
                         <Check className="size-3.5" />
                       )}

frontend/src/components/Flow/FlowDock.tsx

@@ -2,7 +2,6 @@ import { useReactFlow } from "@xyflow/react"
 import {
   AlertCircle,
   Check,
-  Loader2,
   Maximize2,
   Pause,
   Pencil,
@@ -18,6 +17,7 @@ import { useEffect, useState } from "react"
 
 import type { ValidationIssue } from "@/client"
 import { Button } from "@/components/ui/button"
+import { FluksioLoader } from "@/components/ui/fluksio-loader"
 import { Separator } from "@/components/ui/separator"
 import {
   Tooltip,
@@ -273,7 +273,7 @@ export function FlowDock({
                 data-testid="run-flow"
               >
                 {running ? (
-                  <Loader2 className="size-4 animate-spin" />
+                  <FluksioLoader className="size-4" />
                 ) : (
                   <Play className="size-4" />
                 )}
@@ -348,7 +348,7 @@ export function FlowDock({
                 {!connected ? (
                   <WifiOff className="size-3.5" />
                 ) : saving || publishing ? (
-                  <Loader2 className="size-3.5 animate-spin" />
+                  <FluksioLoader className="size-3.5" />
                 ) : (
                   <Check className="size-3.5" />
                 )}

frontend/src/components/ui/fluksio-loader.tsx

@@ -0,0 +1,44 @@
+/**
+ * FluksioLoader: the app's shared loading mark.
+ *
+ * The brand mark — four neurons in a ring — drawn as one continuous stroke
+ * that traces itself and wipes away in a loop (see the `.fluksio-loader-line`
+ * rule + `fluksio-draw` keyframes in index.css, which also guard
+ * `prefers-reduced-motion`: `MotionConfig` covers JS animations, not CSS ones).
+ * Renders a bare <svg> so it drops in for a lucide icon: size it with a
+ * Tailwind `size-*` class and color it via a `text-*` class (everything is
+ * currentColor).
+ */
+
+/**
+ * The ring, clockwise from the top node: a 45° connector, then 270° around the
+ * node it lands on, four times over. Geometry from `assets/fluksio-light.svg`
+ * — same node centres and radius, with the connectors pulled onto the circles
+ * so the whole mark is a single subpath and the dash traces it in one lap.
+ *
+ * Stroke weight is the mark's own 1.5 rather than the weight 2 of the glyphs in
+ * `components/icons/`: at 2 the node rings close up into dots.
+ */
+const RING =
+  "M 13.71 5.84 L 18.16 10.29 A 2.424 2.424 0 1 1 18.16 13.71 L 13.71 18.16 A 2.424 2.424 0 1 1 10.29 18.16 L 5.84 13.71 A 2.424 2.424 0 1 1 5.84 10.29 L 10.29 5.84 A 2.424 2.424 0 1 1 13.71 5.84 Z"
+
+export function FluksioLoader({
+  className,
+  ...props
+}: React.SVGProps<SVGSVGElement>) {
+  return (
+    <svg
+      viewBox="0 0 24 24"
+      fill="none"
+      stroke="currentColor"
+      strokeWidth={1.5}
+      strokeLinecap="round"
+      className={className}
+      role="status"
+      aria-label="Loading"
+      {...props}
+    >
+      <path className="fluksio-loader-line" pathLength={1} d={RING} />
+    </svg>
+  )
+}

frontend/src/components/ui/loading-button.tsx

@@ -1,6 +1,6 @@
 import { Slot, Slottable } from "@radix-ui/react-slot"
 import { cva, type VariantProps } from "class-variance-authority"
-import { Loader2 } from "lucide-react"
+import { FluksioLoader } from "@/components/ui/fluksio-loader"
 import { cn } from "@/lib/utils"
 
 const buttonVariants = cva(
@@ -58,7 +58,7 @@ function LoadingButton({
       disabled={loading || disabled}
       {...props}
     >
-      {loading && <Loader2 className="mr-2 h-5 w-5 animate-spin" />}
+      {loading && <FluksioLoader className="mr-2 h-5 w-5" />}
       <Slottable>{children}</Slottable>
     </Comp>
   )