feat: planchette wander reaches YES/NO, periodically rests on GOODBYE

Wander bounds were tied to the letter ring's radius, which sits inside
YES/NO's corner positions — widened to derive bounds directly from the
board's actual outermost fixed waypoints (YES/NO for the top/sides, the
number row for the bottom) so idle drift covers the whole interactive
board, corners included.

Added a periodic deliberate visit to GOODBYE: every 2-5 minutes
(randomized so multiple open tabs don't sync up), the planchette glides
down and rests there for 3-5 seconds with the same restrained glow used
for ambiently-brushed letters, then resumes normal wander. Purely a
visual beat — no session/game state changes, distinct from an actual
goodbye action.

frontend/src/components/PlanchetteBoard.tsx

@@ -96,6 +96,15 @@ export function PlanchetteBoard({ machine, hue = 150 }: PlanchetteBoardProps) {
     let initialized = false
     const smoke: Smoke[] = []
 
+    // Periodic, deliberate visit to GOODBYE — distinct from the ambient
+    // wander/letter-brushing above: every 2-5 minutes (randomized so
+    // multiple open tabs don't all drift there in lockstep), the planchette
+    // glides down and rests on GOODBYE for a few seconds before resuming
+    // normal idle wander. `t`-relative (seconds since mount), not wall-clock.
+    const randomBetween = (min: number, max: number) => min + Math.random() * (max - min)
+    let nextGoodbyeAt = randomBetween(120, 300)
+    let goodbyeRestUntil = 0
+
     // Spirit knock: an AudioContext created lazily on the first gesture
     // (autoplay policy); a soft tick sounds as each letter is dwelled upon.
     let tickCtx: AudioContext | null = null
@@ -162,17 +171,36 @@ export function PlanchetteBoard({ machine, hue = 150 }: PlanchetteBoardProps) {
       lastKnock = knockKey
 
       // --- target: spelled letter, else idle wander ---
-      // Wander radius is tied directly to the outer letter ring's own
-      // radius/squash (computeLayout's `arc('ABCDEFGHIJKLM', ...)` call) so
-      // the drift genuinely reaches the board's edges — not a fixed
-      // fraction of the canvas that happens to undershoot the ring.
-      const outerRingRadius = Math.min(w * 0.4, h * 0.52)
+      // Wander bounds are tied directly to the board's actual fixed
+      // waypoints — YES/NO (the outermost, topmost points) and the number
+      // row (the lowest) — rather than a derived "ring radius", so idle
+      // drift genuinely covers the full interactive board, corners
+      // included, not just the letter belt.
+      const wanderCx = (layout.yes.x + layout.no.x) / 2
+      const wanderXRange = (layout.no.x - layout.yes.x) / 2
+      const wanderCy = (layout.yes.y + layout.numbers.get('5')!.y) / 2
+      const wanderYRange = (layout.numbers.get('5')!.y - layout.yes.y) / 2
       let target: Point | null = null
+      let restingAtGoodbye = false
       if (snap.current) target = letterTarget(snap.current)
+      if (!target) {
+        if (t >= nextGoodbyeAt && goodbyeRestUntil === 0) {
+          // Arrived at the scheduled moment — begin resting on GOODBYE.
+          goodbyeRestUntil = t + randomBetween(3, 5)
+        }
+        if (goodbyeRestUntil > 0 && t < goodbyeRestUntil) {
+          target = layout.goodbye
+          restingAtGoodbye = true
+        } else if (goodbyeRestUntil > 0) {
+          // Rest just ended — clear it and schedule the next visit.
+          goodbyeRestUntil = 0
+          nextGoodbyeAt = t + randomBetween(120, 300)
+        }
+      }
       if (!target) {
         target = {
-          x: layout.center.x + wander(t, 1.3) * outerRingRadius * 0.94,
-          y: layout.center.y + wander(t * 0.83, 4.1) * outerRingRadius * 0.72 * 0.94,
+          x: wanderCx + wander(t, 1.3) * wanderXRange * 0.96,
+          y: wanderCy + wander(t * 0.83, 4.1) * wanderYRange * 0.96,
         }
       }
       const speed = snap.current ? 0.16 : 0.03
@@ -253,8 +281,20 @@ export function PlanchetteBoard({ machine, hue = 150 }: PlanchetteBoardProps) {
       ctx.fillText('YES', layout.yes.x, layout.yes.y)
       ctx.fillText('NO', layout.no.x, layout.no.y)
       ctx.font = `600 ${Math.max(12, h * 0.03)}px "IBM Plex Mono", monospace`
+      if (restingAtGoodbye) {
+        // Same restrained glow language as an ambiently-brushed letter —
+        // the planchette pausing here is a beat, not an actual "goodbye"
+        // action; nothing about session state changes.
+        ctx.save()
+        ctx.shadowColor = accent
+        ctx.shadowBlur = 12
+        ctx.fillStyle = accent
+        ctx.fillText('G O O D B Y E', layout.goodbye.x, layout.goodbye.y)
+        ctx.restore()
+      } else {
         ctx.fillStyle = `hsla(${hueDeg} 85% 78% / 0.65)`
         ctx.fillText('G O O D B Y E', layout.goodbye.x, layout.goodbye.y)
+      }
 
       // Letters + numbers.
       const hovered = snap.current ?? brushed