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/concat-map/README.markdown

@@ -0,0 +1,62 @@
+concat-map
+==========
+
+Concatenative mapdashery.
+
+[![browser support](http://ci.testling.com/substack/node-concat-map.png)](http://ci.testling.com/substack/node-concat-map)
+
+[![build status](https://secure.travis-ci.org/substack/node-concat-map.png)](http://travis-ci.org/substack/node-concat-map)
+
+example
+=======
+
+``` js
+var concatMap = require('concat-map');
+var xs = [ 1, 2, 3, 4, 5, 6 ];
+var ys = concatMap(xs, function (x) {
+    return x % 2 ? [ x - 0.1, x, x + 0.1 ] : [];
+});
+console.dir(ys);
+```
+
+***
+
+```
+[ 0.9, 1, 1.1, 2.9, 3, 3.1, 4.9, 5, 5.1 ]
+```
+
+methods
+=======
+
+``` js
+var concatMap = require('concat-map')
+```
+
+concatMap(xs, fn)
+-----------------
+
+Return an array of concatenated elements by calling `fn(x, i)` for each element
+`x` and each index `i` in the array `xs`.
+
+When `fn(x, i)` returns an array, its result will be concatenated with the
+result array. If `fn(x, i)` returns anything else, that value will be pushed
+onto the end of the result array.
+
+install
+=======
+
+With [npm](http://npmjs.org) do:
+
+```
+npm install concat-map
+```
+
+license
+=======
+
+MIT
+
+notes
+=====
+
+This module was written while sitting high above the ground in a tree.