Add ansible-managed wifi profiles for meshcore nodes

Each node now gets three NetworkManager wifi connections via a new
wifi role: dotnetwork (home), dotmobile (phone hotspot, for field
troubleshooting), and a host-specific deployed-location network.
Credentials live in a new per-repo ansible-vault (group and host
scoped), matching the pattern already used in dotnetwork.

Also updates the README's Pi imaging instructions from Bookworm to
Trixie, matching what the nodes actually run.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

ansible/host_vars/dm-edworth/vars.yml

@@ -0,0 +1,6 @@
+# Find this by connecting the MeshCore device then running: ls /dev/serial/by-id/
+serial_port: FILL_IN_SERIAL_PORT
+
+# Deployed-location wifi
+wifi_ssid_location: "Ridgeway"
+wifi_password_location: "{{ vault_wifi_location }}"

ansible/host_vars/dm-edworth/vault.yml

@@ -0,0 +1,7 @@
+$ANSIBLE_VAULT;1.1;AES256
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+39613234386161643439613166313962653939343138353539346638316562333330643561333961
+6136343564353736640a623365333930383962333865313938616261373639346435636364313665
+37326636663061383362643261633362643564663531306430633935636636306430353836333338
+3463383931306266393838663734303336383035623733643735