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/eslint/lib/rules/utils/regular-expressions.js

@@ -0,0 +1,58 @@
+/**
+ * @fileoverview Common utils for regular expressions.
+ * @author Josh Goldberg
+ * @author Toru Nagashima
+ */
+
+"use strict";
+
+const { RegExpValidator } = require("@eslint-community/regexpp");
+
+const REGEXPP_LATEST_ECMA_VERSION = 2025;
+
+/**
+ * Checks if the given regular expression pattern would be valid with the `u` flag.
+ * @param {number} ecmaVersion ECMAScript version to parse in.
+ * @param {string} pattern The regular expression pattern to verify.
+ * @param {"u"|"v"} flag The type of Unicode flag
+ * @returns {boolean} `true` if the pattern would be valid with the `u` flag.
+ * `false` if the pattern would be invalid with the `u` flag or the configured
+ * ecmaVersion doesn't support the `u` flag.
+ */
+function isValidWithUnicodeFlag(ecmaVersion, pattern, flag = "u") {
+	if (flag === "u" && ecmaVersion <= 5) {
+		// ecmaVersion <= 5 doesn't support the 'u' flag
+		return false;
+	}
+	if (flag === "v" && ecmaVersion <= 2023) {
+		return false;
+	}
+
+	const validator = new RegExpValidator({
+		ecmaVersion: Math.min(ecmaVersion, REGEXPP_LATEST_ECMA_VERSION),
+	});
+
+	try {
+		validator.validatePattern(
+			pattern,
+			void 0,
+			void 0,
+			flag === "u"
+				? {
+						unicode: /* uFlag = */ true,
+					}
+				: {
+						unicodeSets: true,
+					},
+		);
+	} catch {
+		return false;
+	}
+
+	return true;
+}
+
+module.exports = {
+	isValidWithUnicodeFlag,
+	REGEXPP_LATEST_ECMA_VERSION,
+};