Add post_progress_to_api lightweight telemetry ping

Introduce post_progress_to_api() in misc/api.func — a non-blocking, fire-and-forget curl ping (gated by DIAGNOSTICS and RANDOM_UUID) that updates telemetry status to "configuring". Wire this progress ping into multiple scripts (alpine-install.func, install.func, build.func, core.func) at key milestones (container start, network ready, customization, creation, cleanup) and replace/deduplicate some earlier post_to_api calls. Also update error_handler.func to always report failures immediately via post_update_to_api to ensure failures are captured even before/after container lifecycle.

misc/alpine-install.func

@@ -148,6 +148,7 @@ motd_ssh() {
     # Start the sshd service
     $STD /etc/init.d/sshd start
   fi
+  post_progress_to_api
 }
 
 # Validate Timezone for some LXC's
@@ -184,5 +185,5 @@ EOF
 
   echo "bash -c \"\$(curl -fsSL https://raw.githubusercontent.com/community-scripts/ProxmoxVE/main/ct/${app}.sh)\"" >/usr/bin/update
   chmod +x /usr/bin/update
-
+  post_progress_to_api
 }