chore(deps): update pnpm to v10.26.0 (#2004)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [pnpm](https://pnpm.io)
([source](https://redirect.github.com/pnpm/pnpm/tree/HEAD/pnpm)) |
[`10.25.0` ->
`10.26.0`](https://renovatebot.com/diffs/npm/pnpm/10.25.0/10.26.0) |
![age](https://developer.mend.io/api/mc/badges/age/npm/pnpm/10.26.0?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/pnpm/10.25.0/10.26.0?slim=true)
|

---

### Release Notes

<details>
<summary>pnpm/pnpm (pnpm)</summary>

###
[`v10.26.0`](https://redirect.github.com/pnpm/pnpm/compare/v10.25.0...v10.26.0)

[Compare
Source](https://redirect.github.com/pnpm/pnpm/compare/v10.25.0...v10.26.0)

</details>

---

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---

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---

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desktop/package.json

@@ -5,7 +5,7 @@
   "main": "main.js",
   "repository": "https://code.vikunja.io/desktop",
   "license": "GPL-3.0-or-later",
-  "packageManager": "pnpm@10.25.0",
+  "packageManager": "pnpm@10.26.0",
   "author": {
     "email": "maintainers@vikunja.io",
     "name": "Vikunja Team"

frontend/package.json

@@ -13,7 +13,7 @@
   },
   "homepage": "https://vikunja.io/",
   "funding": "https://opencollective.com/vikunja",
-  "packageManager": "pnpm@10.25.0",
+  "packageManager": "pnpm@10.26.0",
   "engines": {
     "node": ">=24.0.0"
   },