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/postcss-scss/package.json

@@ -0,0 +1,52 @@
+{
+  "name": "postcss-scss",
+  "version": "4.0.9",
+  "description": "SCSS parser for PostCSS",
+  "keywords": [
+    "css",
+    "postcss",
+    "postcss-syntax",
+    "parser",
+    "scss",
+    "sass"
+  ],
+  "author": "Andrey Sitnik <andrey@sitnik.ru>",
+  "license": "MIT",
+  "repository": "postcss/postcss-scss",
+  "engines": {
+    "node": ">=12.0"
+  },
+  "main": "lib/scss-syntax",
+  "types": "lib/scss-syntax.d.ts",
+  "exports": {
+    ".": {
+      "types": "./lib/scss-syntax.d.ts",
+      "require": "./lib/scss-syntax.js",
+      "import": "./lib/scss-syntax.mjs"
+    },
+    "./lib/nested-declaration": "./lib/nested-declaration.js",
+    "./lib/scss-parse": "./lib/scss-parse.js",
+    "./lib/scss-parser": "./lib/scss-parser.js",
+    "./lib/scss-stringifier": "./lib/scss-stringifier.js",
+    "./lib/scss-stringify": "./lib/scss-stringify.js",
+    "./lib/scss-tokenize": "./lib/scss-tokenize.js",
+    "./package.json": "./package.json"
+  },
+  "funding": [
+    {
+      "type": "opencollective",
+      "url": "https://opencollective.com/postcss/"
+    },
+    {
+      "type": "tidelift",
+      "url": "https://tidelift.com/funding/github/npm/postcss-scss"
+    },
+    {
+      "type": "github",
+      "url": "https://github.com/sponsors/ai"
+    }
+  ],
+  "peerDependencies": {
+    "postcss": "^8.4.29"
+  }
+}