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/valid-each-key.js

@@ -0,0 +1,50 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const utils_1 = require("../utils");
+const ast_utils_1 = require("../utils/ast-utils");
+exports.default = (0, utils_1.createRule)('valid-each-key', {
+    meta: {
+        docs: {
+            description: 'enforce keys to use variables defined in the `{#each}` block',
+            category: 'Best Practices',
+            // TODO Switch to recommended in the major version.
+            recommended: false
+        },
+        schema: [],
+        messages: {
+            keyUseEachVars: 'Expected key to use the variables which are defined by the `{#each}` block.'
+        },
+        type: 'suggestion'
+    },
+    create(context) {
+        return {
+            SvelteEachBlock(node) {
+                if (node.key == null) {
+                    return;
+                }
+                const scope = (0, ast_utils_1.getScope)(context, node.key);
+                for (const variable of scope.variables) {
+                    if (!variable.defs.some((def) => (node.context.range[0] <= def.name.range[0] &&
+                        def.name.range[1] <= node.context.range[1]) ||
+                        (node.index &&
+                            node.index.range[0] <= def.name.range[0] &&
+                            def.name.range[1] <= node.index.range[1]))) {
+                        // It's not an iteration variable.
+                        continue;
+                    }
+                    for (const reference of variable.references) {
+                        if (node.key.range[0] <= reference.identifier.range[0] &&
+                            reference.identifier.range[1] <= node.key.range[1]) {
+                            // A variable is used in the key.
+                            return;
+                        }
+                    }
+                }
+                context.report({
+                    node: node.key,
+                    messageId: 'keyUseEachVars'
+                });
+            }
+        };
+    }
+});