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/eslint-plugin-svelte/lib/rules/no-restricted-html-elements.js

@@ -0,0 +1,64 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const utils_1 = require("../utils");
+exports.default = (0, utils_1.createRule)('no-restricted-html-elements', {
+    meta: {
+        docs: {
+            description: 'disallow specific HTML elements',
+            category: 'Stylistic Issues',
+            recommended: false,
+            conflictWithPrettier: false
+        },
+        schema: {
+            type: 'array',
+            items: {
+                oneOf: [
+                    { type: 'string' },
+                    {
+                        type: 'object',
+                        properties: {
+                            elements: {
+                                type: 'array',
+                                items: {
+                                    type: ['string']
+                                },
+                                uniqueItems: true,
+                                minItems: 1
+                            },
+                            message: { type: 'string', minLength: 1 }
+                        },
+                        additionalProperties: false,
+                        minItems: 1
+                    }
+                ]
+            },
+            uniqueItems: true,
+            minItems: 1
+        },
+        messages: {},
+        type: 'suggestion'
+    },
+    create(context) {
+        return {
+            SvelteElement(node) {
+                if (node.kind !== 'html')
+                    return;
+                const { name } = node;
+                if (name.type !== 'SvelteName')
+                    return;
+                for (const option of context.options) {
+                    const message = option.message || `Unexpected use of forbidden HTML element ${name.name}.`;
+                    const elements = option.elements || [option];
+                    for (const element of elements) {
+                        if (element === name.name) {
+                            context.report({
+                                message,
+                                node: node.startTag
+                            });
+                        }
+                    }
+                }
+            }
+        };
+    }
+});