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/combined-stream/lib/combined_stream.js

@@ -0,0 +1,208 @@
+var util = require('util');
+var Stream = require('stream').Stream;
+var DelayedStream = require('delayed-stream');
+
+module.exports = CombinedStream;
+function CombinedStream() {
+  this.writable = false;
+  this.readable = true;
+  this.dataSize = 0;
+  this.maxDataSize = 2 * 1024 * 1024;
+  this.pauseStreams = true;
+
+  this._released = false;
+  this._streams = [];
+  this._currentStream = null;
+  this._insideLoop = false;
+  this._pendingNext = false;
+}
+util.inherits(CombinedStream, Stream);
+
+CombinedStream.create = function(options) {
+  var combinedStream = new this();
+
+  options = options || {};
+  for (var option in options) {
+    combinedStream[option] = options[option];
+  }
+
+  return combinedStream;
+};
+
+CombinedStream.isStreamLike = function(stream) {
+  return (typeof stream !== 'function')
+    && (typeof stream !== 'string')
+    && (typeof stream !== 'boolean')
+    && (typeof stream !== 'number')
+    && (!Buffer.isBuffer(stream));
+};
+
+CombinedStream.prototype.append = function(stream) {
+  var isStreamLike = CombinedStream.isStreamLike(stream);
+
+  if (isStreamLike) {
+    if (!(stream instanceof DelayedStream)) {
+      var newStream = DelayedStream.create(stream, {
+        maxDataSize: Infinity,
+        pauseStream: this.pauseStreams,
+      });
+      stream.on('data', this._checkDataSize.bind(this));
+      stream = newStream;
+    }
+
+    this._handleErrors(stream);
+
+    if (this.pauseStreams) {
+      stream.pause();
+    }
+  }
+
+  this._streams.push(stream);
+  return this;
+};
+
+CombinedStream.prototype.pipe = function(dest, options) {
+  Stream.prototype.pipe.call(this, dest, options);
+  this.resume();
+  return dest;
+};
+
+CombinedStream.prototype._getNext = function() {
+  this._currentStream = null;
+
+  if (this._insideLoop) {
+    this._pendingNext = true;
+    return; // defer call
+  }
+
+  this._insideLoop = true;
+  try {
+    do {
+      this._pendingNext = false;
+      this._realGetNext();
+    } while (this._pendingNext);
+  } finally {
+    this._insideLoop = false;
+  }
+};
+
+CombinedStream.prototype._realGetNext = function() {
+  var stream = this._streams.shift();
+
+
+  if (typeof stream == 'undefined') {
+    this.end();
+    return;
+  }
+
+  if (typeof stream !== 'function') {
+    this._pipeNext(stream);
+    return;
+  }
+
+  var getStream = stream;
+  getStream(function(stream) {
+    var isStreamLike = CombinedStream.isStreamLike(stream);
+    if (isStreamLike) {
+      stream.on('data', this._checkDataSize.bind(this));
+      this._handleErrors(stream);
+    }
+
+    this._pipeNext(stream);
+  }.bind(this));
+};
+
+CombinedStream.prototype._pipeNext = function(stream) {
+  this._currentStream = stream;
+
+  var isStreamLike = CombinedStream.isStreamLike(stream);
+  if (isStreamLike) {
+    stream.on('end', this._getNext.bind(this));
+    stream.pipe(this, {end: false});
+    return;
+  }
+
+  var value = stream;
+  this.write(value);
+  this._getNext();
+};
+
+CombinedStream.prototype._handleErrors = function(stream) {
+  var self = this;
+  stream.on('error', function(err) {
+    self._emitError(err);
+  });
+};
+
+CombinedStream.prototype.write = function(data) {
+  this.emit('data', data);
+};
+
+CombinedStream.prototype.pause = function() {
+  if (!this.pauseStreams) {
+    return;
+  }
+
+  if(this.pauseStreams && this._currentStream && typeof(this._currentStream.pause) == 'function') this._currentStream.pause();
+  this.emit('pause');
+};
+
+CombinedStream.prototype.resume = function() {
+  if (!this._released) {
+    this._released = true;
+    this.writable = true;
+    this._getNext();
+  }
+
+  if(this.pauseStreams && this._currentStream && typeof(this._currentStream.resume) == 'function') this._currentStream.resume();
+  this.emit('resume');
+};
+
+CombinedStream.prototype.end = function() {
+  this._reset();
+  this.emit('end');
+};
+
+CombinedStream.prototype.destroy = function() {
+  this._reset();
+  this.emit('close');
+};
+
+CombinedStream.prototype._reset = function() {
+  this.writable = false;
+  this._streams = [];
+  this._currentStream = null;
+};
+
+CombinedStream.prototype._checkDataSize = function() {
+  this._updateDataSize();
+  if (this.dataSize <= this.maxDataSize) {
+    return;
+  }
+
+  var message =
+    'DelayedStream#maxDataSize of ' + this.maxDataSize + ' bytes exceeded.';
+  this._emitError(new Error(message));
+};
+
+CombinedStream.prototype._updateDataSize = function() {
+  this.dataSize = 0;
+
+  var self = this;
+  this._streams.forEach(function(stream) {
+    if (!stream.dataSize) {
+      return;
+    }
+
+    self.dataSize += stream.dataSize;
+  });
+
+  if (this._currentStream && this._currentStream.dataSize) {
+    this.dataSize += this._currentStream.dataSize;
+  }
+};
+
+CombinedStream.prototype._emitError = function(err) {
+  this._reset();
+  this.emit('error', err);
+};