feat: Complete fleet — 94 skills across 10+ domains

Pulled ALL skills from 15 source repositories:
- anthropics/skills: 16 (docs, design, MCP, testing)
- obra/superpowers: 14 (TDD, debugging, agents, planning)
- coreyhaines31/marketingskills: 25 (marketing, CRO, SEO, growth)
- better-auth/skills: 5 (auth patterns)
- vercel-labs/agent-skills: 5 (React, design, Vercel)
- antfu/skills: 16 (Vue, Vite, Vitest, pnpm, Turborepo)
- Plus 13 individual skills from various repos

Mosaic Stack is not limited to coding — the Orchestrator and
subagents serve coding, business, design, marketing, writing,
logistics, analysis, and more.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

skills/vueuse-functions/references/useObservable.md

@@ -0,0 +1,67 @@
+---
+category: '@RxJS'
+---
+
+# useObservable
+
+Use an RxJS [`Observable`](https://rxjs.dev/guide/observable), return a `ref`, and automatically unsubscribe from it when the component is unmounted.
+
+## Usage
+
+<!-- TODO: import rxjs error if enable twoslash -->
+
+```ts no-twoslash
+import { useObservable } from '@vueuse/rxjs'
+import { interval } from 'rxjs'
+import { mapTo, scan, startWith } from 'rxjs/operators'
+
+// setup()
+const count = useObservable(
+  interval(1000).pipe(
+    mapTo(1),
+    startWith(0),
+    scan((total, next) => next + total),
+  ),
+)
+```
+
+If you want to add custom error handling to an `Observable` that might error, you can supply an optional `onError` configuration. Without this, RxJS will treat any error in the supplied `Observable` as an "unhandled error" and it will be thrown in a new call stack and reported to `window.onerror` (or `process.on('error')` if you happen to be in Node).
+
+```ts no-twoslash
+import { useObservable } from '@vueuse/rxjs'
+import { interval } from 'rxjs'
+import { map } from 'rxjs/operators'
+
+// setup()
+const count = useObservable(
+  interval(1000).pipe(
+    map((n) => {
+      if (n === 10)
+        throw new Error('oops')
+
+      return n + n
+    }),
+  ),
+  {
+    onError: (err) => {
+      console.log(err.message) // "oops"
+    },
+  },
+)
+```
+
+## Type Declarations
+
+```ts
+export interface UseObservableOptions<I> {
+  onError?: (err: any) => void
+  /**
+   * The value that should be set if the observable has not emitted.
+   */
+  initialValue?: I | undefined
+}
+export declare function useObservable<H, I = undefined>(
+  observable: Observable<H>,
+  options?: UseObservableOptions<I | undefined>,
+): Readonly<Ref<H | I>>
+```