Readme.md contains confusing suggestions for rclone.conf

The Readme.md could use some improvement regarding rclone.conf file. The examples suggest using a file mount, however, rclone requires write access to the file and creates a new temporary file when making updates, so a directory mount seems to be necessary.

There are multiple references:

An example mount is given in the _rclone backup method_ section:
`- ./rclone.config:/config/rclone/rclone.conf:ro`

This is mounting the file itself, however, rclone creates a new temporary file when it edits the rclone.conf file, so a folder mount seems to be necessary. Also, the source file is named rclone.con**fig** and this may be confusing.

Another reference exists in the _Restic with rclone_ section:
```
volumes:
# mount volume pre-configured using a host mounted file
- ./rclone.conf:/config/rclone/rclone.conf
```
It will be helpful to also point out that the mount needs to be mounted rw.

Lastly, a _Troubleshooting_ section that mentions "setting the environment variable `DEBUG` to `true`" may be useful for readers.

Read the Readme.md sections named “rclone backup method,” “Restic with rclone,” and “Troubleshooting.” Update the examples and explanatory text to reflect the required writable directory mount, the rclone.conf naming difference, and the DEBUG environment variable guidance. Done means all referenced examples are consistent and no longer suggest an unsuitable read-only file mount.

Written by the indexing model from the issue text.