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/nodes/identity.js

@@ -0,0 +1,53 @@
+'use strict';
+
+const ALIAS = Symbol.for('yaml.alias');
+const DOC = Symbol.for('yaml.document');
+const MAP = Symbol.for('yaml.map');
+const PAIR = Symbol.for('yaml.pair');
+const SCALAR = Symbol.for('yaml.scalar');
+const SEQ = Symbol.for('yaml.seq');
+const NODE_TYPE = Symbol.for('yaml.node.type');
+const isAlias = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === ALIAS;
+const isDocument = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === DOC;
+const isMap = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === MAP;
+const isPair = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === PAIR;
+const isScalar = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === SCALAR;
+const isSeq = (node) => !!node && typeof node === 'object' && node[NODE_TYPE] === SEQ;
+function isCollection(node) {
+    if (node && typeof node === 'object')
+        switch (node[NODE_TYPE]) {
+            case MAP:
+            case SEQ:
+                return true;
+        }
+    return false;
+}
+function isNode(node) {
+    if (node && typeof node === 'object')
+        switch (node[NODE_TYPE]) {
+            case ALIAS:
+            case MAP:
+            case SCALAR:
+            case SEQ:
+                return true;
+        }
+    return false;
+}
+const hasAnchor = (node) => (isScalar(node) || isCollection(node)) && !!node.anchor;
+
+exports.ALIAS = ALIAS;
+exports.DOC = DOC;
+exports.MAP = MAP;
+exports.NODE_TYPE = NODE_TYPE;
+exports.PAIR = PAIR;
+exports.SCALAR = SCALAR;
+exports.SEQ = SEQ;
+exports.hasAnchor = hasAnchor;
+exports.isAlias = isAlias;
+exports.isCollection = isCollection;
+exports.isDocument = isDocument;
+exports.isMap = isMap;
+exports.isNode = isNode;
+exports.isPair = isPair;
+exports.isScalar = isScalar;
+exports.isSeq = isSeq;