0.10.0: Archify Sync, optional live collaboration on a model

Several people edit one model at once through a server you run yourself
(archify-vscode-ext-sync); the files stay ordinary files on each disk.
Sign-in through the browser, offline-first with later merge, teammates'
cursors in the Source view and text editors, and a Shared section on the
model page with people, versions, Compare and Restore.

Without a server nothing changes: the sync code is a separate bundle that
loads only when a model is shared, after a sign-in, or when a sync command
or invite link is used.

src/sync/protocol.ts

@@ -0,0 +1,60 @@
+// What the extension and the Archify Sync server agree on. Mirrors
+// `packages/protocol` (generated from Rust) in archify-vscode-ext-sync; keep
+// both in step when the protocol changes.
+
+export const PROTOCOL_VERSION = 1;
+/** Root map of a space's Yjs document: model-root-relative POSIX path → Y.Text. */
+export const FILES_MAP = 'files';
+/** The link file in a model root: names server and space, holds no secrets. */
+export const LINK_FILE = '.archify-sync';
+
+export type OrgRole = 'admin' | 'member';
+export type SpaceRole = 'owner' | 'editor';
+export type VersionKind = 'snapshot' | 'publish' | 'restore';
+
+export interface ApiError { error: string; message: string }
+export interface Account { id: string; organisation_id: string; name: string; display_name: string; role: OrgRole }
+export interface TokenResponse { access_token: string; expires_in: number; refresh_token: string; account: Account }
+export interface ServerInfo { name: string; version: string; protocol: number; set_up: boolean }
+export interface Space { id: string; name: string; role: SpaceRole; created_at: string }
+export interface Member { account_id: string; name: string; display_name: string; role: SpaceRole }
+export interface Invite { token: string; url: string; expires_at: string }
+export interface JoinResponse { space: Space }
+export interface Version {
+  id: number;
+  major: number;
+  minor: number;
+  kind: VersionKind;
+  name: string | null;
+  created_by: string | null;
+  created_at: string;
+  restored_from: number | null;
+}
+export interface VersionFiles { version: Version; files: { path: string; text: string }[] }
+
+/** The contents of `.archify-sync`. */
+export interface Link {
+  server: string;
+  space: string;
+  name?: string;
+}
+
+export function parseLink(text: string): Link | undefined {
+  try {
+    const value = JSON.parse(text) as Partial<Link>;
+    if (typeof value.server === 'string' && typeof value.space === 'string' && /^[0-9a-f-]{36}$/i.test(value.space)) {
+      return { server: value.server.replace(/\/+$/, ''), space: value.space, name: typeof value.name === 'string' ? value.name : undefined };
+    }
+  } catch {
+    // not a link
+  }
+  return undefined;
+}
+
+export function formatLink(link: Link): string {
+  return `${JSON.stringify({ server: link.server, space: link.space, name: link.name }, null, 2)}\n`;
+}
+
+export function versionLabel(v: Version): string {
+  return `${v.major}.${v.minor}`;
+}