Injured wild rat in our front garden

This morning we found a rat lying on our front porch, not moving much and breathing shallowly. We just didn’t know what to do, so we left her in the shade hoping she’d just recover or pass?? Cut to this evening, she’s somehow moved about a foot into the garden, still moving. I couldn’t take it anymore and brought her some lettuce and a shallow dish of water. She immediately responded, but it looks like she can’t move her back legs.

I tried stroking her with a little piece of cardboard. Anything above the “waist” seems to distress her, anything below she doesn’t really react to.

I don’t know what to do. I have a dachshund so I can’t bring her inside and have nothing to offer protection for the night. She has food and I refilled the water. Idk if I’m just delaying the inevitable in a cruel way, or if I’m delusional thinking I’ll take her to the vet tomorrow…?

Ive had pet rats in the past and she reminds me so much of my first. What do I do?

Sorry if this isn’t allowed. I know the rules allow for wild rat posts sometimes. I was hoping this would qualify. I just don’t want this sweet girl to suffer.