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/svelte-toolbelt/dist/utils/style-to-css.js

@@ -0,0 +1,23 @@
+function createParser(matcher, replacer) {
+    const regex = RegExp(matcher, "g");
+    return (str) => {
+        // throw an error if not a string
+        if (typeof str !== "string") {
+            throw new TypeError(`expected an argument of type string, but got ${typeof str}`);
+        }
+        // if no match between string and matcher
+        if (!str.match(regex))
+            return str;
+        // executes the replacer function for each match
+        return str.replace(regex, replacer);
+    };
+}
+const camelToKebab = createParser(/[A-Z]/, (match) => `-${match.toLowerCase()}`);
+export function styleToCSS(styleObj) {
+    if (!styleObj || typeof styleObj !== "object" || Array.isArray(styleObj)) {
+        throw new TypeError(`expected an argument of type object, but got ${typeof styleObj}`);
+    }
+    return Object.keys(styleObj)
+        .map((property) => `${camelToKebab(property)}: ${styleObj[property]};`)
+        .join("\n");
+}