fix(sw): ship self-unregistering tombstone to kill stale Void 1 service worker

CHANGELOG.md

@@ -3,6 +3,9 @@
 All notable changes to Void 2.0 are documented here.
 Format: [Keep a Changelog](https://keepachangelog.com).
 
+## 2.0.0-alpha.22 — Kill the stale Void 1 service worker
+- **Self-unregistering `/sw.js` tombstone** (`public/sw.js`): Void 1 registered a caching service worker at this origin; it persisted across the cutover and served stale assets to returning visitors (immune to hard reload, since an active SW sits in front of the browser cache). Void 2 ships no SW, so the old one was never replaced. This tombstone is picked up by the browser's SW update check, then clears all caches, unregisters itself, and reloads open tabs — self-healing every device that ever ran Void 1. Root cause of "the Wiki still shows projects/tasks and isn't sectioned" despite the docs-mode + ordering code being correctly deployed.
+
 ## 2.0.0-alpha.21 — Docs-kind spaces + long-page embedding
 - **`spaces.kind` (`'project'` | `'docs'`)** (`migration 021`): `'docs'` spaces render as a pure documentation repository — `public/views/space.js` shows only the sectioned page tree (no Projects/Tasks/"+ New"), and the sidebar expands a docs space to its top-level pages (`#/page/:id`) instead of projects. The **Wiki** is seeded to `'docs'`. Project spaces unchanged.
 - **Chunk + mean-pool embeddings** (`lib/ai/ollama.js` `chunkText`/`embedTextPooled`, used by the embed worker): long pages are split into ≤1500-char chunks, each embedded, then element-wise mean-pooled into one vector — replacing the old `slice(0,6000)` truncation that made dense/long docs fail with Ollama "input length exceeds context length". Single-chunk docs are unchanged.