feat(release): switch to Homebrew cask distribution and update install docs

- migrate from brew formula to homebrew_casks in GoReleaser
- update tap and install commands to use --cask
- adjust repository and directory for cask support
- update commit message template for cask releases
- clean up README formatting and install paths
- improve wording for cross-platform installation and releases

Author: programmersd21

.goreleaser.yaml

@@ -73,22 +73,16 @@ release:
   draft: false
   prerelease: auto
 
-brews:
+homebrew_casks:
   - repository:
       owner: programmersd21
-      name: homebrew-kairo
+      name: kairo
 
-    directory: Formula
+    directory: HomebrewCask
 
-    commit_msg_template: "Brew formula update for {{ .ProjectName }} {{ .Tag }}"
+    commit_msg_template: "Brew cask update for {{ .ProjectName }} {{ .Tag }}"
 
     homepage: "https://github.com/programmersd21/kairo"
     description: "Minimal, powerful task management"
     license: "MIT"
-
-    test: |
-      system "#{bin}/kairo", "--version"
-
-    install: |
-      bin.install "kairo"
-      
+    

HomebrewCask/.gitkeep

@@ -71,8 +71,8 @@ Built with [Bubble Tea](https://github.com/charmbracelet/bubbletea) (TUI framewo
 ### macOS (Homebrew)
 
 ```bash
-brew tap programmersd21/kairo
-brew install kairo
+brew tap programmersd21/kairo https://github.com/programmersd21/kairo
+brew install --cask programmersd21/kairo/kairo
 ```
 
 ### Linux / macOS (curl)
@@ -89,15 +89,15 @@ Installs to `$HOME/.local/bin/kairo` (fallback: `/usr/local/bin/kairo`) and atte
 iwr -useb https://raw.githubusercontent.com/programmersd21/kairo/main/scripts/install.ps1 | iex
 ```
 
-Installs to `%USERPROFILE%\\AppData\\Local\\Programs\\kairo\\kairo.exe` and adds the install directory to your user PATH.
+Installs to `%USERPROFILE%\AppData\Local\Programs\kairo\kairo.exe` and adds the install directory to your user PATH.
 
-## For any OS out of these:
+### Any other OS
 
 ```bash
 go install github.com/programmersd21/kairo/cmd/kairo@latest
 ```
 
-**OR** use the [PREBUILTS](https://https://github.com/programmersd21/kairo/releases).
+**OR** download a prebuilt binary from the [Releases page](https://github.com/programmersd21/kairo/releases).
 
 ### Updates