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/ajv/lib/dot/defaults.def

@@ -0,0 +1,47 @@
+{{## def.assignDefault:
+  {{? it.compositeRule }}
+    {{
+      if (it.opts.strictDefaults) {
+        var $defaultMsg = 'default is ignored for: ' + $passData;
+        if (it.opts.strictDefaults === 'log') it.logger.warn($defaultMsg);
+        else throw new Error($defaultMsg);
+      }
+    }}
+  {{??}}
+    if ({{=$passData}} === undefined
+      {{? it.opts.useDefaults == 'empty' }}
+        || {{=$passData}} === null
+        || {{=$passData}} === ''
+      {{?}}
+    )
+      {{=$passData}} = {{? it.opts.useDefaults == 'shared' }}
+                         {{= it.useDefault($sch.default) }}
+                       {{??}}
+                         {{= JSON.stringify($sch.default) }}
+                       {{?}};
+  {{?}}
+#}}
+
+
+{{## def.defaultProperties:
+  {{
+    var $schema = it.schema.properties
+      , $schemaKeys = Object.keys($schema); }}
+  {{~ $schemaKeys:$propertyKey }}
+    {{ var $sch = $schema[$propertyKey]; }}
+    {{? $sch.default !== undefined }}
+      {{ var $passData = $data + it.util.getProperty($propertyKey); }}
+      {{# def.assignDefault }}
+    {{?}}
+  {{~}}
+#}}
+
+
+{{## def.defaultItems:
+  {{~ it.schema.items:$sch:$i }}
+    {{? $sch.default !== undefined }}
+      {{ var $passData = $data + '[' + $i + ']'; }}
+      {{# def.assignDefault }}
+    {{?}}
+  {{~}}
+#}}