So connecting from Windows, you are able to connect properly?
You can also find the cifs guide in documentation. It lists various commands on how to successfully mount the network share. Search the documentation.
/dev/root on /rom type squashfs (ro,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,noatime)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,noatime)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noatime)
/dev/mtdblock6 on /overlay type jffs2 (rw,noatime)
overlayfs:/overlay on / type overlay (rw,noatime,lowerdir=/,upperdir=/overlay/upper,workdir=/overlay/work)
tmpfs on /dev type tmpfs (rw,nosuid,relatime,size=512k,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
debugfs on /sys/kernel/debug type debugfs (rw,noatime)
What type of device you're mounting to your router? I don't see any device being mounted on /mnt.
Secondly, your configuration is itself misleading, no wonder you're having issues. In /etc/config/samba you have openwrt as user but in smbd.conf you have root. I would strongly advise you to remove any content you have added in smbd.conf and keep it in default shape. You should only edit /etc/config/samba with proper config from LuCI and remove any input from users field and allow guests and then see how it goes. Once you have it working you can move to advance use cases.
In your config the interface is set to lo br-lan which means both loopback and lan. So it should work on both interfaces. Also as I said before it's best to start from default config for your use case and, once everything starts working, work yoir way up to what you want to achieve. This will make sure you dont get in problems in the future.
You are limiting SMB to v1 via max protocol = SMB1, but since 10 months Windows 10 disables/uninstalls SMBv1 support by default, because its a old protocol with security problems.
So you either have to delete this line and allow the default SMBv2 as max protocol or enable SMBv1 support in Windows 10 via Control Panel "Programs and Features/Turn Windows Features on or off/SMB 1.0 ...".
PS: the snapshots builds have Samba4 support with SMBv3 support, which is the default for Windows 10 machines.