Unable to access HTTP pi-hole web interface on local network

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Your debug log shows Pi-hole is configured to try ports 80 and 443, but they are marked as optional (o flag):

   [webserver]
     port = "80o,443os,[::]:80o,[::]:443os"

That means: if ports 80 and 443 are already in use, the web server won't be started... and that's exactly what happened.

Ports 80 and 443 are in use by Caddy.
Pi-hole web server is not using any ports:

*** [ DIAGNOSING ]: Ports in use
[✗] udp:*:443 is in use by caddy
...
    tcp:0.0.0.0:8080 is in use by docker-proxy
    tcp:[::]:8080 is in use by docker-proxy
...
[✗] tcp:*:443 is in use by caddy
[✗] tcp:*:80 is in use by caddy

Solution 1:
If you want to keep Caddy running, you need to change Pi-hole ports to something else. Port 8080 is also in use by docker. I will use ports 8880 and 8443, but you can use any free port.

Run this command to change the ports:

sudo pihole-FTL --config webserver.port '8880o,8443os'

And access the web interface including the port on the URL:

Solution 2:
If you don't need Caddy, disable (or uninstall) it and then restart Pi-hole.
After Caddy is disabled, the ports will be free and Pi-hole will use them without the need to change the configuration. No ports will be needed on the URL.