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/js-yaml/lib/schema.js

@@ -0,0 +1,109 @@
+'use strict'
+
+const YAMLException = require('./exception')
+const Type = require('./type')
+
+function compileList (schema, name) {
+  const result = []
+
+  schema[name].forEach(function (currentType) {
+    let newIndex = result.length
+
+    result.forEach(function (previousType, previousIndex) {
+      if (previousType.tag === currentType.tag &&
+          previousType.kind === currentType.kind &&
+          previousType.multi === currentType.multi) {
+        newIndex = previousIndex
+      }
+    })
+
+    result[newIndex] = currentType
+  })
+
+  return result
+}
+
+function compileMap (/* lists... */) {
+  const result = {
+    scalar: {},
+    sequence: {},
+    mapping: {},
+    fallback: {},
+    multi: {
+      scalar: [],
+      sequence: [],
+      mapping: [],
+      fallback: []
+    }
+  }
+  function collectType (type) {
+    if (type.multi) {
+      result.multi[type.kind].push(type)
+      result.multi['fallback'].push(type)
+    } else {
+      result[type.kind][type.tag] = result['fallback'][type.tag] = type
+    }
+  }
+
+  for (let index = 0, length = arguments.length; index < length; index += 1) {
+    arguments[index].forEach(collectType)
+  }
+  return result
+}
+
+function Schema (definition) {
+  return this.extend(definition)
+}
+
+Schema.prototype.extend = function extend (definition) {
+  let implicit = []
+  let explicit = []
+
+  if (definition instanceof Type) {
+    // Schema.extend(type)
+    explicit.push(definition)
+  } else if (Array.isArray(definition)) {
+    // Schema.extend([ type1, type2, ... ])
+    explicit = explicit.concat(definition)
+  } else if (definition && (Array.isArray(definition.implicit) || Array.isArray(definition.explicit))) {
+    // Schema.extend({ explicit: [ type1, type2, ... ], implicit: [ type1, type2, ... ] })
+    if (definition.implicit) implicit = implicit.concat(definition.implicit)
+    if (definition.explicit) explicit = explicit.concat(definition.explicit)
+  } else {
+    throw new YAMLException('Schema.extend argument should be a Type, [ Type ], ' +
+      'or a schema definition ({ implicit: [...], explicit: [...] })')
+  }
+
+  implicit.forEach(function (type) {
+    if (!(type instanceof Type)) {
+      throw new YAMLException('Specified list of YAML types (or a single Type object) contains a non-Type object.')
+    }
+
+    if (type.loadKind && type.loadKind !== 'scalar') {
+      throw new YAMLException('There is a non-scalar type in the implicit list of a schema. Implicit resolving of such types is not supported.')
+    }
+
+    if (type.multi) {
+      throw new YAMLException('There is a multi type in the implicit list of a schema. Multi tags can only be listed as explicit.')
+    }
+  })
+
+  explicit.forEach(function (type) {
+    if (!(type instanceof Type)) {
+      throw new YAMLException('Specified list of YAML types (or a single Type object) contains a non-Type object.')
+    }
+  })
+
+  const result = Object.create(Schema.prototype)
+
+  result.implicit = (this.implicit || []).concat(implicit)
+  result.explicit = (this.explicit || []).concat(explicit)
+
+  result.compiledImplicit = compileList(result, 'implicit')
+  result.compiledExplicit = compileList(result, 'explicit')
+  result.compiledTypeMap = compileMap(result.compiledImplicit, result.compiledExplicit)
+
+  return result
+}
+
+module.exports = Schema