feat(canvas): fullscreen Railway-style workspace canvas

Rebuild the project canvas as a full-viewport graph instead of a boxed
66vh panel. Slim workspace top bar now holds the view tabs, project meta
and actions; the canvas fills all remaining space.

- Floating glass controls: env filter + group pill (top-left), zoom out /
  live zoom % / zoom in / fit / tidy pill (bottom-left), dark MiniMap
  (bottom-right), hint chip, demo badge.
- Inspector panel: selecting a node opens a right-side glass panel with
  status, image, address, inferred connections incl. variable reasons,
  and deploy/restart/stop/delete actions. Esc or pane click closes.
- Auto-layout: dependency-depth layered layout (consumers left,
  datastores right) for first-visit placement and the Tidy action.
  Unpositioned services park right of existing bounds, not at (0,0).
- Nodes: fixed 240px width (was 210 vs 220-280 CSS mismatch), per-type
  icons/colors incl. cron, spinner icon while deploying, hover lift.
- Edges: lime bezier strokes, animated dashes while either endpoint is
  deploying, hover glow updated from stale purple to accent.
- Groups: off-brand crimson replaced with accent tokens, double-click
  title to rename inline.
- Keyboard: F fit, 0 reset zoom, +/- zoom, Esc deselect. Marquee select
  on Shift-drag. Double-click zoom disabled, dead connection drags off.
- Mobile: icon-only tabs, minimap/hint hidden under md.
- Retake docs/screenshots/canvas.png + site copy (1600x900 demo).

Authored By: TDvorak <[email protected]>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/frontend/src/features/workspace/model.ts

@@ -44,14 +44,17 @@ export const DEFAULT_VIEWPORT: CanvasViewport = {
   zoom: 1,
 };
 
-export function createDefaultCanvasMetadata(services: ServiceEntity[]): ProjectCanvasMetadata {
+export function createDefaultCanvasMetadata(
+  services: ServiceEntity[],
+  layout?: Map<string, CanvasPoint>,
+): ProjectCanvasMetadata {
   const nodes = services.map((service, index) => {
     const col = index % 3;
     const row = Math.floor(index / 3);
 
     return {
       serviceId: service.id,
-      position: {
+      position: layout?.get(service.id) ?? {
         x: 70 + col * 260,
         y: 80 + row * 170,
       },