feat(homebrew): migrate from Formula to Cask

Switch GoReleaser config from `brews` to `homebrew_casks` and update
documentation links to reference Casks/go-task.rb instead of
Formula/go-task.rb.

.goreleaser.yml

@@ -80,21 +80,20 @@ nfpms:
       - src: completion/zsh/_task
         dst: /usr/local/share/zsh/site-functions/_task
 
-brews:
+homebrew_casks:
   - name: go-task
     description: A fast, cross-platform build tool inspired by Make, designed for modern workflows.
-    license: MIT
     homepage: https://taskfile.dev
-    directory: Formula
+    binaries:
+      - task
+    completions:
+      bash: completion/bash/task.bash
+      zsh: completion/zsh/_task
+      fish: completion/fish/task.fish
+    directory: Casks
     repository:
       owner: go-task
       name: homebrew-tap
-    test: system "#{bin}/task", "--help"
-    install: |-
-      bin.install "task"
-      bash_completion.install "completion/bash/task.bash" => "task"
-      zsh_completion.install "completion/zsh/_task" => "_task"
-      fish_completion.install "completion/fish/task.fish"
     commit_author:
       name: task-bot
       email: 106601941+task-bot@users.noreply.github.com

website/src/docs/installation.md

@@ -59,7 +59,7 @@ confidence.
 ### [Homebrew](https://brew.sh) ![macOS](https://img.shields.io/badge/MacOS-000000?logo=apple&logoColor=F0F0F0) ![Linux](https://img.shields.io/badge/Linux-FCC624?logo=linux&logoColor=black) {#homebrew}
 
 Task is available via our official Homebrew tap
-[[source](https://github.com/go-task/homebrew-tap/blob/main/Formula/go-task.rb)]:
+[[source](https://github.com/go-task/homebrew-tap/blob/main/Casks/go-task.rb)]:
 
 ```shell
 brew install go-task/tap/go-task

website/src/docs/releasing.md

@@ -23,7 +23,7 @@ defined in the above GitHub Actions.
 ## Homebrew
 
 Goreleaser will automatically push a new commit to the
-[Formula/go-task.rb][gotaskrb] file in the [Homebrew tap][homebrewtap]
+[Casks/go-task.rb][gotaskrb] file in the [Homebrew tap][homebrewtap]
 repository to release the new version.
 
 ## npm
@@ -66,7 +66,7 @@ If you think its Task version is outdated, open an issue to let us know.
 
 [goreleaser]: https://goreleaser.com/
 [homebrewtap]: https://github.com/go-task/homebrew-tap
-[gotaskrb]: https://github.com/go-task/homebrew-tap/blob/main/Formula/go-task.rb
+[gotaskrb]: https://github.com/go-task/homebrew-tap/blob/main/Casks/go-task.rb
 [packagejson]: https://github.com/go-task/task/blob/main/package.json#L3
 [snappackage]: https://github.com/go-task/snap
 [snapcraftyaml]: