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/source-map-js/lib/array-set.js

@@ -0,0 +1,121 @@
+/* -*- Mode: js; js-indent-level: 2; -*- */
+/*
+ * Copyright 2011 Mozilla Foundation and contributors
+ * Licensed under the New BSD license. See LICENSE or:
+ * http://opensource.org/licenses/BSD-3-Clause
+ */
+
+var util = require('./util');
+var has = Object.prototype.hasOwnProperty;
+var hasNativeMap = typeof Map !== "undefined";
+
+/**
+ * A data structure which is a combination of an array and a set. Adding a new
+ * member is O(1), testing for membership is O(1), and finding the index of an
+ * element is O(1). Removing elements from the set is not supported. Only
+ * strings are supported for membership.
+ */
+function ArraySet() {
+  this._array = [];
+  this._set = hasNativeMap ? new Map() : Object.create(null);
+}
+
+/**
+ * Static method for creating ArraySet instances from an existing array.
+ */
+ArraySet.fromArray = function ArraySet_fromArray(aArray, aAllowDuplicates) {
+  var set = new ArraySet();
+  for (var i = 0, len = aArray.length; i < len; i++) {
+    set.add(aArray[i], aAllowDuplicates);
+  }
+  return set;
+};
+
+/**
+ * Return how many unique items are in this ArraySet. If duplicates have been
+ * added, than those do not count towards the size.
+ *
+ * @returns Number
+ */
+ArraySet.prototype.size = function ArraySet_size() {
+  return hasNativeMap ? this._set.size : Object.getOwnPropertyNames(this._set).length;
+};
+
+/**
+ * Add the given string to this set.
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.add = function ArraySet_add(aStr, aAllowDuplicates) {
+  var sStr = hasNativeMap ? aStr : util.toSetString(aStr);
+  var isDuplicate = hasNativeMap ? this.has(aStr) : has.call(this._set, sStr);
+  var idx = this._array.length;
+  if (!isDuplicate || aAllowDuplicates) {
+    this._array.push(aStr);
+  }
+  if (!isDuplicate) {
+    if (hasNativeMap) {
+      this._set.set(aStr, idx);
+    } else {
+      this._set[sStr] = idx;
+    }
+  }
+};
+
+/**
+ * Is the given string a member of this set?
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.has = function ArraySet_has(aStr) {
+  if (hasNativeMap) {
+    return this._set.has(aStr);
+  } else {
+    var sStr = util.toSetString(aStr);
+    return has.call(this._set, sStr);
+  }
+};
+
+/**
+ * What is the index of the given string in the array?
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.indexOf = function ArraySet_indexOf(aStr) {
+  if (hasNativeMap) {
+    var idx = this._set.get(aStr);
+    if (idx >= 0) {
+        return idx;
+    }
+  } else {
+    var sStr = util.toSetString(aStr);
+    if (has.call(this._set, sStr)) {
+      return this._set[sStr];
+    }
+  }
+
+  throw new Error('"' + aStr + '" is not in the set.');
+};
+
+/**
+ * What is the element at the given index?
+ *
+ * @param Number aIdx
+ */
+ArraySet.prototype.at = function ArraySet_at(aIdx) {
+  if (aIdx >= 0 && aIdx < this._array.length) {
+    return this._array[aIdx];
+  }
+  throw new Error('No element indexed by ' + aIdx);
+};
+
+/**
+ * Returns the array representation of this set (which has the proper indices
+ * indicated by indexOf). Note that this is a copy of the internal array used
+ * for storing the members so that no one can mess with internal state.
+ */
+ArraySet.prototype.toArray = function ArraySet_toArray() {
+  return this._array.slice();
+};
+
+exports.ArraySet = ArraySet;