Redesign the resume site as a 3D-editor viewport

New design: studio backdrop with a perspective floor and X/Z axis lines, an
orientation gizmo that orbits on scroll, Bricolage Grotesque and Instrument
Sans (bundled, no build-time network). Projects are laid out as plates by a
row planner that keeps every row full for any count; a demo image from the
repo root is shown when present, otherwise a generated voxel sculpture.
Text and projects still come live from Gitea.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XtcZtnG4GQA1d6mW5PNrS9

lib/plan.ts

@@ -0,0 +1,39 @@
+export type Span = 2 | 3 | 4 | 6
+
+/**
+ * Column spans (out of 6) for `count` projects, so that every row is exactly full whatever the count:
+ * rows of two or three, a feature row first, and never a lone project in the last row (a single project
+ * spans the whole width). Two-project rows alternate 4+2 and 2+4 for rhythm.
+ */
+export function planSpans(count: number): Span[] {
+  if (count <= 0) return []
+  if (count === 1) return [6]
+
+  const sizes: number[] = []
+  const pattern = [2, 3, 3]
+  let remaining = count
+  for (let i = 0; remaining > 0; i++) {
+    const size = Math.min(pattern[i % pattern.length], remaining)
+    sizes.push(size)
+    remaining -= size
+  }
+
+  const last = sizes.length - 1
+  if (sizes[last] === 1) {
+    if (sizes[last - 1] === 3) {
+      sizes[last - 1] = 2
+      sizes[last] = 2
+    } else {
+      sizes[last - 1] = 3
+      sizes.pop()
+    }
+  }
+
+  const spans: Span[] = []
+  let pairs = 0
+  for (const size of sizes) {
+    if (size === 3) spans.push(2, 2, 2)
+    else spans.push(...(pairs++ % 2 === 0 ? ([4, 2] as const) : ([2, 4] as const)))
+  }
+  return spans
+}