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/browser/dist/index.js

@@ -0,0 +1,17 @@
+export { Composer } from './compose/composer.js';
+export { Document } from './doc/Document.js';
+export { Schema } from './schema/Schema.js';
+export { YAMLError, YAMLParseError, YAMLWarning } from './errors.js';
+export { Alias } from './nodes/Alias.js';
+export { isAlias, isCollection, isDocument, isMap, isNode, isPair, isScalar, isSeq } from './nodes/identity.js';
+export { Pair } from './nodes/Pair.js';
+export { Scalar } from './nodes/Scalar.js';
+export { YAMLMap } from './nodes/YAMLMap.js';
+export { YAMLSeq } from './nodes/YAMLSeq.js';
+import * as cst from './parse/cst.js';
+export { cst as CST };
+export { Lexer } from './parse/lexer.js';
+export { LineCounter } from './parse/line-counter.js';
+export { Parser } from './parse/parser.js';
+export { parse, parseAllDocuments, parseDocument, stringify } from './public-api.js';
+export { visit, visitAsync } from './visit.js';