feat: audit phase 6 (T3) — Journey Mode, a guided career narrative

Browsing a skill tree is entirely self-directed: a visitor has to know what
to click and in what order, and most won't. The strongest material (WebRTC
signaling, MediaPipe accessibility, air-gapped deployment tooling) sat
several clicks deep with nothing pointing at it.

Journey Mode flies the camera along the experience arc oldest-first — so the
career reads as progression rather than a résumé's reverse chronology —
surfacing up to two highlights per stop.

- New utils/journey.ts: stops derived from data.ts, so the tour can never
  drift from the tree. 12 unit tests cover ordering (oldest-first), that only
  real jobs appear (no container nodes), that it ends on the current role,
  slug uniqueness, and deep-link resolution.
- New JourneyMode.svelte: progress pips, prev/next/pause, keyboard
  (arrows/space/escape), focus moved into the panel and restored on exit,
  aria-live so each stop is announced as the tour advances.
- Deep-linkable: ?tour=peraton opens on that role, ?tour on its own starts
  from the beginning. Slug matching is case- and punctuation-insensitive.
- panToNode now takes a target scale and duration, so each stop settles at a
  readable zoom rather than wherever the user left it. It also re-baselines
  the parallax origin on completion, and drives updateLabels during the
  flight so labels stay in step.
- Launch from the HUD ("Take the 60-second tour") or the J key. The keyboard
  handler yields entirely to the journey while it runs, as it already did
  for the search palette.

Reduced motion starts the tour paused rather than auto-advancing —
auto-advancing content that moves the camera is precisely what that
preference is asking us not to do — and panToNode jumps instead of flying.
The tour stays fully available, just user-driven.

Fixed while verifying: the first-run coach hint occupies the same
bottom-centre slot and was rendering on top of the journey's controls. It now
yields while the tour is active, and starting a tour retires it.

Verified in the production build: ?tour=peraton lands on stop 6/6 with the
camera on the Peraton node; Next/Prev/Pause all step correctly (1/6 -> 2/6 ->
3/6 -> back to 2/6); focus lands in the panel; the hint is suppressed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/lib/pixi/interaction.ts

@@ -325,24 +325,50 @@ export function attachPanZoom(
  * Centre the view on a node in tree-space. Used by the accessible tree
  * navigator so keyboard focus and the canvas stay in sync.
  */
-export function panToNode(ctrl: SkillTreeController, x: number, y: number, life: Lifecycle) {
+export function panToNode(
+	ctrl: SkillTreeController,
+	x: number,
+	y: number,
+	life: Lifecycle,
+	options: { scale?: number; duration?: number } = {}
+) {
 	const { app, treeContainer } = ctrl;
-	const scale = treeContainer.scale.x;
-	const targetX = app.screen.width / 2 - x * scale;
-	const targetY = app.screen.height / 2 - y * scale;
+	const targetScale = options.scale ?? treeContainer.scale.x;
+	const targetX = app.screen.width / 2 - x * targetScale;
+	const targetY = app.screen.height / 2 - y * targetScale;
+
+	// Reduced motion jumps instead of flying — the objection is to the camera
+	// movement, not to being taken somewhere.
+	const duration = prefersReducedMotion() ? 0 : (options.duration ?? 0.4);
 
 	life.animate(() => {
+		const sync = () => {
+			updateParallax(ctrl);
+			updateLabels(ctrl);
+		};
+
 		gsap.to(treeContainer, {
 			x: targetX,
 			y: targetY,
-			duration: prefersReducedMotion() ? 0 : 0.4,
-			ease: 'power2.out',
+			duration,
+			ease: 'power2.inOut',
 			overwrite: 'auto',
-			onUpdate: () => {
-				updateParallax(ctrl);
-				updateLabels(ctrl);
+			onUpdate: sync,
+			onComplete: () => {
+				// Re-baseline parallax so later panning stays consistent.
+				ctrl.initialTreeX = treeContainer.x;
+				ctrl.initialTreeY = treeContainer.y;
 			}
 		});
+
+		gsap.to(treeContainer.scale, {
+			x: targetScale,
+			y: targetScale,
+			duration,
+			ease: 'power2.inOut',
+			overwrite: 'auto',
+			onUpdate: sync
+		});
 	});
 }
 
@@ -351,6 +377,9 @@ interface KeyboardOpts {
 	/** Cmd/Ctrl-K — open the search palette. */
 	onOpenSearch: () => void;
 	isSearchOpen: () => boolean;
+	/** 'J' — start the guided career journey. */
+	onStartJourney: () => void;
+	isJourneyActive: () => boolean;
 	onCloseModal: () => void;
 	isModalVisible: () => boolean;
 	isStatsVisible: () => boolean;
@@ -384,8 +413,8 @@ export function attachKeyboard(ctrl: SkillTreeController, opts: KeyboardOpts, li
 			return;
 		}
 
-		// While the palette is open it owns the keyboard entirely.
-		if (opts.isSearchOpen()) return;
+		// While the palette or the guided journey is open, it owns the keyboard.
+		if (opts.isSearchOpen() || opts.isJourneyActive()) return;
 
 		if (e.ctrlKey || e.metaKey || e.altKey) return;
 
@@ -472,6 +501,13 @@ export function attachKeyboard(ctrl: SkillTreeController, opts: KeyboardOpts, li
 			updateLabels(ctrl);
 		}
 
+		// J starts the guided career journey.
+		if (e.key === 'j' || e.key === 'J') {
+			e.preventDefault();
+			opts.onStartJourney();
+			return;
+		}
+
 		// L forces labels on/off regardless of zoom.
 		if (e.key === 'l' || e.key === 'L') {
 			e.preventDefault();