[BUG]: Cache key ignores auth state, causing stale contributor data after adding PAT

### Bug Description

`fetchWithCache()` in `src/services/github.js` caches responses using only the URL as key, ignoring `pat`. Since `fetchContributors` uses `maxPages = pat ? 10 : 1`, page=1 has the same URL whether authenticated or not. Once page=1 is cached without a PAT, adding a PAT later silently returns the old cached page=1 instead of re-fetching with auth. Affects `fetchOrg`, `fetchRepos`, `fetchContributors`, `fetchIssues`, `fetchPulls`.

### Steps to Reproduce

1. Without a PAT, explore an org (e.g. AOSSIE-Org) — caches page=1 contributors for each repo.
2. Add a PAT in Settings, Save.
3. Explore the same org again.
4. In DevTools → Network, filter by a repo already explored in step 1 (e.g. "Website").
5. page=1 shows no new request (served from cache); only page=2, page=3... appear as fresh requests.

### Logs and Screenshots

async function fetchWithCache(url, pat) {
const cached = await cacheGet(url) // <-- pat ignored here
if (cached) return cached
...
const data = await res.json()
cacheSet(url, data) // <-- pat ignored here too
return data
}

### Environment Details

_No response_

### Impact

Critical - Application is unusable

### Code of Conduct

- [x] I have joined the [Discord server](https://discord.gg/hjUhu33uAn) and will post updates there
- [x] I have searched existing issues to avoid duplicates

Start in src/services/github.js at fetchWithCache(), then trace its use from fetchOrg, fetchRepos, fetchContributors, fetchIssues, and fetchPulls. Reproduce the unauthenticated-then-authenticated sequence described in the issue and inspect cacheGet/cacheSet behavior. Done means page=1 is fetched again after a PAT is added instead of being served from the unauthenticated cache.

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