Rename to uv (#1302)

First, replace all usages in files in-place. I used my editor for this.
If someone wants to add a one-liner that'd be fun.

Then, update directory and file names:

```
# Run twice for nested directories
find . -type d -print0 | xargs -0 rename s/puffin/uv/g
find . -type d -print0 | xargs -0 rename s/puffin/uv/g

# Update files
find . -type f -print0 | xargs -0 rename s/puffin/uv/g
```

Then add all the files again

```
# Add all the files again
git add crates
git add python/uv

# This one needs a force-add
git add -f crates/uv-trampoline
```

.github/workflows/build-docker.yml

@@ -19,7 +19,7 @@ on:
 
 jobs:
   docker-publish:
-    name: Build Docker image (ghcr.io/astral-sh/puffin)
+    name: Build Docker image (ghcr.io/astral-sh/uv)
     runs-on: ubuntu-latest
     environment:
       name: release
@@ -40,7 +40,7 @@ jobs:
         id: meta
         uses: docker/metadata-action@v5
         with:
-          images: ghcr.io/astral-sh/puffin
+          images: ghcr.io/astral-sh/uv
 
       - name: Check tag consistency
         if: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}
@@ -64,5 +64,5 @@ jobs:
           cache-from: type=gha
           cache-to: type=gha,mode=max
           push: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}
-          tags: ghcr.io/astral-sh/puffin:latest,ghcr.io/astral-sh/puffin:${{ (inputs.plan != '' && fromJson(inputs.plan).announcement_tag) || 'dry-run' }}
+          tags: ghcr.io/astral-sh/uv:latest,ghcr.io/astral-sh/uv:${{ (inputs.plan != '' && fromJson(inputs.plan).announcement_tag) || 'dry-run' }}
           labels: ${{ steps.meta.outputs.labels }}