Stop the delegated frontend build from sudoing on the control machine

pi_standard_setup's defaults set `ansible_become: true`. Role defaults are
play-wide host variables, and in Ansible's precedence the `ansible_become`
variable outranks the `become` keyword - so the `become: false` on every
pi_musicmouse task delegated to localhost was silently overridden and each one
tried to sudo on the machine running ansible:

    Premature end of stream waiting for become success or become password prompt

Those defaults earn their keep bootstrapping a fresh Pi, where you connect as
`pi` and become root to enable root login, so override the variable on the
delegated tasks rather than removing them.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

roles/pi_musicmouse/tasks/main.yml

@@ -119,6 +119,14 @@
     mode: "0755"
   delegate_to: localhost
   become: false
+  vars:
+    # `become: false` above is not enough on its own. pi_standard_setup's defaults set
+    # `ansible_become: true`, role defaults are play-wide host variables, and the
+    # `ansible_become` *variable* outranks the `become` *keyword* in Ansible's
+    # precedence - so every task here tried to sudo on the control machine. Those
+    # defaults are needed to bootstrap a fresh Pi (connect as `pi`, become root, enable
+    # root login), so override the variable here rather than removing them.
+    ansible_become: false
 
 - name: Checkout Musicmouse repo for frontend build (control machine)
   ansible.builtin.git:
@@ -129,6 +137,8 @@
     force: true
   delegate_to: localhost
   become: false
+  vars:
+    ansible_become: false  # see the first delegated task in tasks/main.yml
   notify: Build frontend
 
 - name: Samba setup