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/rrweb-cssom/README.mdown

@@ -0,0 +1,74 @@
+# CSSOM
+
+CSSOM.js is a CSS parser written in pure JavaScript. It is also a partial implementation of [CSS Object Model](http://dev.w3.org/csswg/cssom/). 
+
+    CSSOM.parse("body {color: black}")
+    -> {
+      cssRules: [
+        {
+          selectorText: "body",
+          style: {
+            0: "color",
+            color: "black",
+            length: 1
+          }
+        }
+      ]
+    }
+
+
+## [Parser demo](http://nv.github.io/CSSOM/docs/parse.html)
+
+Works well in Google Chrome 6+, Safari 5+, Firefox 3.6+, Opera 10.63+.
+Doesn't work in IE < 9 because of unsupported getters/setters.
+
+To use CSSOM.js in the browser you might want to build a one-file version that exposes a single `CSSOM` global variable:
+
+    ➤ git clone https://github.com/NV/CSSOM.git
+    ➤ cd CSSOM
+    ➤ node build.js
+    build/CSSOM.js is done
+
+To use it with Node.js or any other CommonJS loader:
+
+    ➤ npm install cssom
+
+## Why is this not maintained?
+
+1. I no longer use it in my projects
+2. Even though cssom npm package has 26 million weekly downloads (as of April 17, 2023), I haven't made a dollar from my work.
+
+If you want specific issues to be resolved, you can hire me for $100 per hour (which is 1/2 of my normal rate).
+
+## Don’t use it if...
+
+You parse CSS to mungle, minify or reformat code like this:
+
+```css
+div {
+  background: gray;
+  background: linear-gradient(to bottom, white 0%, black 100%);
+}
+```
+
+This pattern is often used to give browsers that don’t understand linear gradients a fallback solution (e.g. gray color in the example).
+In CSSOM, `background: gray` [gets overwritten](http://nv.github.io/CSSOM/docs/parse.html#css=div%20%7B%0A%20%20%20%20%20%20background%3A%20gray%3B%0A%20%20%20%20background%3A%20linear-gradient(to%20bottom%2C%20white%200%25%2C%20black%20100%25)%3B%0A%7D).
+It does **NOT** get preserved.
+
+If you do CSS mungling, minification, or image inlining, considere using one of the following:
+
+  * [postcss](https://github.com/postcss/postcss)
+  * [reworkcss/css](https://github.com/reworkcss/css)
+  * [csso](https://github.com/css/csso)
+  * [mensch](https://github.com/brettstimmerman/mensch)
+
+
+## [Tests](http://nv.github.com/CSSOM/spec/)
+
+To run tests locally:
+
+    ➤ git submodule init
+    ➤ git submodule update
+
+
+## [Who uses CSSOM.js](https://github.com/NV/CSSOM/wiki/Who-uses-CSSOM.js)