feat: Phase 1 — extract the client (web SPA + desktop) to dtoro/oikos-web

Problem: the hexagonal refactor churns the backend tree for nine more
phases; the UI delivery stack (web/ SPA, cmd/desktop Wails wrapper,
compose/web image) must move to its own repo first so doc/layout
rewrites land once on a backend-only tree.

Change:
- New repo git.hubris.network/dtoro/oikos-web (v0.33.0): web/, desktop/
  (updateURL repointed to oikos-web releases), compose/, own CI (web +
  desktop jobs), own deploy script (CI-green gate, TOCTOU guard,
  version-tagged images, prune-to-3), own webhook receiver on :9798 +
  launchd unit, own compose project publishing the same 8091:80.
- Cutover executed on mac-mini in order: oikos stack's web service
  stopped+removed, oikos-web project brought up on 8091; outer Caddy
  untouched (targets the published port) — serving + Authentik flow +
  /wails 404 quirk verified post-cutover.
- Stripped from oikos: web/, cmd/desktop/, compose/web/, desktop CI
  workflow, ci.yml web job, Makefile ui/desktop/desktop-package/install
  targets, the compose web service, oikos-web from deploy.sh's fallback
  prune list; wails + go-keyring dropped from go.mod, vendor synced.
- README / CONTRIBUTING / AGENTS.md / .agents dev+operations docs now
  point at the new repo; mbse + mascot design docs carry a path note.

Risk: production SPA serving depends on the new pipeline now; rollback
is versioned-image re-up of the old web service from a pre-split
checkout (port 8091). Desktop builds installed before the split still
check dtoro/oikos releases — one manual reinstall, noted in the
oikos-web release notes.

Verification: go vet, make test (race), make generate-check, golangci
(no new findings; baseline down 400→365); post-cutover curls —
localhost:8091 200, /wails/runtime.js 404, outer Caddy 302 Authentik.

web/node_modules/ws/lib/subprotocol.js

@@ -0,0 +1,62 @@
+'use strict';
+
+const { tokenChars } = require('./validation');
+
+/**
+ * Parses the `Sec-WebSocket-Protocol` header into a set of subprotocol names.
+ *
+ * @param {String} header The field value of the header
+ * @return {Set} The subprotocol names
+ * @public
+ */
+function parse(header) {
+  const protocols = new Set();
+  let start = -1;
+  let end = -1;
+  let i = 0;
+
+  for (i; i < header.length; i++) {
+    const code = header.charCodeAt(i);
+
+    if (end === -1 && tokenChars[code] === 1) {
+      if (start === -1) start = i;
+    } else if (
+      i !== 0 &&
+      (code === 0x20 /* ' ' */ || code === 0x09) /* '\t' */
+    ) {
+      if (end === -1 && start !== -1) end = i;
+    } else if (code === 0x2c /* ',' */) {
+      if (start === -1) {
+        throw new SyntaxError(`Unexpected character at index ${i}`);
+      }
+
+      if (end === -1) end = i;
+
+      const protocol = header.slice(start, end);
+
+      if (protocols.has(protocol)) {
+        throw new SyntaxError(`The "${protocol}" subprotocol is duplicated`);
+      }
+
+      protocols.add(protocol);
+      start = end = -1;
+    } else {
+      throw new SyntaxError(`Unexpected character at index ${i}`);
+    }
+  }
+
+  if (start === -1 || end !== -1) {
+    throw new SyntaxError('Unexpected end of input');
+  }
+
+  const protocol = header.slice(start, i);
+
+  if (protocols.has(protocol)) {
+    throw new SyntaxError(`The "${protocol}" subprotocol is duplicated`);
+  }
+
+  protocols.add(protocol);
+  return protocols;
+}
+
+module.exports = { parse };