top-langs fails with theme or custom colors

### Describe the bug

When using the **`top-langs`** card via `readme-tools/github-readme-stats-action@v1` the action crashes with:

`TypeError: Cannot use 'in' operator to search for 'border_color' in undefined`

The error occurs consistently when:

- a valid theme is set (e.g. `dracula`, `github_dark`)
- custom colors are used without a theme

Interestingly, the card **does not fail** when an **invalid theme name** is provided ... I accidentally tried `github_dar` and it worked.

---

**Tested option configurations:**
Fails – valid theme
...&layout=compact&langs_count=9&theme=dracula

Fails – custom colors without theme
...&layout=compact&langs_count=9&title_color=628fdb&text_color=36b2a5&bg_color=1a1b27

Fails – custom colors with valid theme
...&layout=compact&langs_count=9&theme=github_dark&title_color=628fdb&text_color=36b2a5&bg_color=1a1b27

Fails – minimal config
...&layout=compact&langs_count=9

**Works** – invalid theme name
...&layout=compact&langs_count=9&theme=github_dar

---

I'm pretty sure that's a bug because I've read the readme and it says "You can customize the appearance and behavior of the top languages card using the [common options](https://github.com/anuraghazra/github-readme-stats?tab=readme-ov-file#common-options) and exclusive options listed in the table below." so it should work I guess

### Expected behavior

Theme or at least custom colors should be applied and the svg should build without errors

### Screenshots / Live demo link

You can check my [runs](https://github.com/binnichtaktiv/binnichtaktiv/actions/runs/21707180561) and [commits](https://github.com/binnichtaktiv/binnichtaktiv/commits/main/.github/workflows/main.yml)

### Additional context

If I forgot some info pls lmk I'll send asap

Reproduce the failure with the listed top-langs configurations, including a valid theme, custom colors, and minimal options, using the linked workflow run as reference. Trace the top-langs card generation from those inputs and verify that valid themes, custom colors, and minimal configuration produce an SVG without the reported TypeError.

Written by the indexing model from the issue text.