* Update internal-ui-mounts.mdx
For sys/internal/ui/mounts:
Make it clear that this endpoint is not only being leveraged on the Web UI, but is also leveraged in other places such as `command/kv_helpers.go` for example. Also update response to standard Vault API response JSON, not just `data` portion of response, and include options data present on KV v2 mounts.
For sys/internal/ui/mounts/:path:
Add initial version of this endpoint family.
* docs(website/content/api-docs/system/internal): backwards compatibility disclaimer
* realign MD table
* restrict response sample to data portion to be in line with other docs
* docs(website/content/api-docs/system/internal): ui/mounts calling mode notes