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/yaml/dist/schema/yaml-1.1/binary.js

@@ -0,0 +1,70 @@
+'use strict';
+
+var node_buffer = require('buffer');
+var Scalar = require('../../nodes/Scalar.js');
+var stringifyString = require('../../stringify/stringifyString.js');
+
+const binary = {
+    identify: value => value instanceof Uint8Array, // Buffer inherits from Uint8Array
+    default: false,
+    tag: 'tag:yaml.org,2002:binary',
+    /**
+     * Returns a Buffer in node and an Uint8Array in browsers
+     *
+     * To use the resulting buffer as an image, you'll want to do something like:
+     *
+     *   const blob = new Blob([buffer], { type: 'image/jpeg' })
+     *   document.querySelector('#photo').src = URL.createObjectURL(blob)
+     */
+    resolve(src, onError) {
+        if (typeof node_buffer.Buffer === 'function') {
+            return node_buffer.Buffer.from(src, 'base64');
+        }
+        else if (typeof atob === 'function') {
+            // On IE 11, atob() can't handle newlines
+            const str = atob(src.replace(/[\n\r]/g, ''));
+            const buffer = new Uint8Array(str.length);
+            for (let i = 0; i < str.length; ++i)
+                buffer[i] = str.charCodeAt(i);
+            return buffer;
+        }
+        else {
+            onError('This environment does not support reading binary tags; either Buffer or atob is required');
+            return src;
+        }
+    },
+    stringify({ comment, type, value }, ctx, onComment, onChompKeep) {
+        if (!value)
+            return '';
+        const buf = value; // checked earlier by binary.identify()
+        let str;
+        if (typeof node_buffer.Buffer === 'function') {
+            str =
+                buf instanceof node_buffer.Buffer
+                    ? buf.toString('base64')
+                    : node_buffer.Buffer.from(buf.buffer).toString('base64');
+        }
+        else if (typeof btoa === 'function') {
+            let s = '';
+            for (let i = 0; i < buf.length; ++i)
+                s += String.fromCharCode(buf[i]);
+            str = btoa(s);
+        }
+        else {
+            throw new Error('This environment does not support writing binary tags; either Buffer or btoa is required');
+        }
+        type ?? (type = Scalar.Scalar.BLOCK_LITERAL);
+        if (type !== Scalar.Scalar.QUOTE_DOUBLE) {
+            const lineWidth = Math.max(ctx.options.lineWidth - ctx.indent.length, ctx.options.minContentWidth);
+            const n = Math.ceil(str.length / lineWidth);
+            const lines = new Array(n);
+            for (let i = 0, o = 0; i < n; ++i, o += lineWidth) {
+                lines[i] = str.substr(o, lineWidth);
+            }
+            str = lines.join(type === Scalar.Scalar.BLOCK_LITERAL ? '\n' : ' ');
+        }
+        return stringifyString.stringifyString({ comment, type, value: str }, ctx, onComment, onChompKeep);
+    }
+};
+
+exports.binary = binary;