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/mapping-list.js

@@ -0,0 +1,79 @@
+/* -*- Mode: js; js-indent-level: 2; -*- */
+/*
+ * Copyright 2014 Mozilla Foundation and contributors
+ * Licensed under the New BSD license. See LICENSE or:
+ * http://opensource.org/licenses/BSD-3-Clause
+ */
+
+var util = require('./util');
+
+/**
+ * Determine whether mappingB is after mappingA with respect to generated
+ * position.
+ */
+function generatedPositionAfter(mappingA, mappingB) {
+  // Optimized for most common case
+  var lineA = mappingA.generatedLine;
+  var lineB = mappingB.generatedLine;
+  var columnA = mappingA.generatedColumn;
+  var columnB = mappingB.generatedColumn;
+  return lineB > lineA || lineB == lineA && columnB >= columnA ||
+         util.compareByGeneratedPositionsInflated(mappingA, mappingB) <= 0;
+}
+
+/**
+ * A data structure to provide a sorted view of accumulated mappings in a
+ * performance conscious manner. It trades a neglibable overhead in general
+ * case for a large speedup in case of mappings being added in order.
+ */
+function MappingList() {
+  this._array = [];
+  this._sorted = true;
+  // Serves as infimum
+  this._last = {generatedLine: -1, generatedColumn: 0};
+}
+
+/**
+ * Iterate through internal items. This method takes the same arguments that
+ * `Array.prototype.forEach` takes.
+ *
+ * NOTE: The order of the mappings is NOT guaranteed.
+ */
+MappingList.prototype.unsortedForEach =
+  function MappingList_forEach(aCallback, aThisArg) {
+    this._array.forEach(aCallback, aThisArg);
+  };
+
+/**
+ * Add the given source mapping.
+ *
+ * @param Object aMapping
+ */
+MappingList.prototype.add = function MappingList_add(aMapping) {
+  if (generatedPositionAfter(this._last, aMapping)) {
+    this._last = aMapping;
+    this._array.push(aMapping);
+  } else {
+    this._sorted = false;
+    this._array.push(aMapping);
+  }
+};
+
+/**
+ * Returns the flat, sorted array of mappings. The mappings are sorted by
+ * generated position.
+ *
+ * WARNING: This method returns internal data without copying, for
+ * performance. The return value must NOT be mutated, and should be treated as
+ * an immutable borrow. If you want to take ownership, you must make your own
+ * copy.
+ */
+MappingList.prototype.toArray = function MappingList_toArray() {
+  if (!this._sorted) {
+    this._array.sort(util.compareByGeneratedPositionsInflated);
+    this._sorted = true;
+  }
+  return this._array;
+};
+
+exports.MappingList = MappingList;