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/postcss/lib/warning.d.ts

@@ -0,0 +1,146 @@
+import { RangePosition } from './css-syntax-error.js'
+import Node from './node.js'
+
+declare namespace Warning {
+  export interface WarningOptions {
+    /**
+     * End position, exclusive, in CSS node string that caused the warning.
+     */
+    end?: RangePosition
+
+    /**
+     * End index, exclusive, in CSS node string that caused the warning.
+     */
+    endIndex?: number
+
+    /**
+     * Start index, inclusive, in CSS node string that caused the warning.
+     */
+    index?: number
+
+    /**
+     * CSS node that caused the warning.
+     */
+    node?: Node
+
+    /**
+     * Name of the plugin that created this warning. `Result#warn` fills
+     * this property automatically.
+     */
+    plugin?: string
+
+    /**
+     * Start position, inclusive, in CSS node string that caused the warning.
+     */
+    start?: RangePosition
+
+    /**
+     * Word in CSS source that caused the warning.
+     */
+    word?: string
+  }
+
+  export { Warning_ as default }
+}
+
+/**
+ * Represents a plugin’s warning. It can be created using `Node#warn`.
+ *
+ * ```js
+ * if (decl.important) {
+ *   decl.warn(result, 'Avoid !important', { word: '!important' })
+ * }
+ * ```
+ */
+declare class Warning_ {
+  /**
+   * Column for inclusive start position in the input file with this warning’s source.
+   *
+   * ```js
+   * warning.column //=> 6
+   * ```
+   */
+  column: number
+
+  /**
+   * Column for exclusive end position in the input file with this warning’s source.
+   *
+   * ```js
+   * warning.endColumn //=> 4
+   * ```
+   */
+  endColumn?: number
+
+  /**
+   * Line for exclusive end position in the input file with this warning’s source.
+   *
+   * ```js
+   * warning.endLine //=> 6
+   * ```
+   */
+  endLine?: number
+
+  /**
+   * Line for inclusive start position in the input file with this warning’s source.
+   *
+   * ```js
+   * warning.line //=> 5
+   * ```
+   */
+  line: number
+
+  /**
+   * Contains the CSS node that caused the warning.
+   *
+   * ```js
+   * warning.node.toString() //=> 'color: white !important'
+   * ```
+   */
+  node: Node
+
+  /**
+   * The name of the plugin that created this warning.
+   * When you call `Node#warn` it will fill this property automatically.
+   *
+   * ```js
+   * warning.plugin //=> 'postcss-important'
+   * ```
+   */
+  plugin: string
+
+  /**
+   * The warning message.
+   *
+   * ```js
+   * warning.text //=> 'Try to avoid !important'
+   * ```
+   */
+  text: string
+
+  /**
+   * Type to filter warnings from `Result#messages`.
+   * Always equal to `"warning"`.
+   */
+  type: 'warning'
+
+  /**
+   * @param text Warning message.
+   * @param opts Warning options.
+   */
+  constructor(text: string, opts?: Warning.WarningOptions)
+
+  /**
+   * Returns a warning position and message.
+   *
+   * ```js
+   * warning.toString() //=> 'postcss-lint:a.css:10:14: Avoid !important'
+   * ```
+   *
+   * @return Warning position and message.
+   */
+  toString(): string
+}
+
+declare class Warning extends Warning_ {}
+
+export = Warning