feat: add fallback for invalid URL when combining with suffix

[xinyun2020]

Description

This change adds a fallback mechanism when constructing a combined URL using this.data.url and an optional urlSuffix.
Previously, if this.data.url was invalid or not a proper base URL, the code would throw an exception without trying to use the suffix and fail to load the frame source.

Now:

• It first tries to construct a URL from this.data.url.
• If that fails, it falls back to concatenating the base and suffix directly.
• It then merges search parameters, pathname, and hash between the base URL and suffix safely.

This ensures frames still load even when the provided base URL is incomplete or invalid.

Also adds the ability to embed any website easily using the same configuration.

Use case

```custom-frames
frame: https
style: height: 500px; width: 100%;
urlSuffix: www.google.com/
```

Risk

• Low: Affects only frame initialization logic.