bin/: add task (go-task) Taskfile runner

Pinned to v3.52.0, installed as a static release binary into ~/.local/bin
like the other tools. The release tarball has the binary at its root, so
the existing install_tarball_bin helper covers it.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

bin/install.sh

@@ -126,6 +126,16 @@ install_tofu() {
   mark_version tofu "$ver"
 }
 
+# task — go-task, the Taskfile.yml task runner. Binary is at the archive root.
+install_task() {
+  ver=v3.52.0
+  have_version task "$ver" && { fsay "task $ver already installed."; return 0; }
+  install_tarball_bin \
+    "https://github.com/go-task/task/releases/download/$ver/task_linux_$DEB.tar.gz" \
+    task task
+  mark_version task "$ver"
+}
+
 # terragrunt — thin wrapper around tofu/terraform (single static binary).
 install_terragrunt() {
   ver=v1.1.0
@@ -150,6 +160,7 @@ install_kubens
 install_stern
 install_yq
 install_tofu
+install_task
 install_terragrunt
 
 fsay "Done. Tools in $BIN_DIR (added to PATH by zsh/zshrc)."