fix(cli): tauri add NPM packages for community plugins (#12246)

It currently isn't possible to simply add a community plugin the same was as adding official plugins.
Trying to perform  `npm run tauri add tauri-plugin-python` is trying to install npm package `@tauri-apps/plugin-python`.
But the npm scope `@tauri-apps/` is reserved for official tauri plugins.

The official documentation recommends to name the npm package `tauri-plugin-{name}-api` and it should be possible to have a parameter that makes it possible to install that package.

- closes #12217

This changes the command to check if the plugin is an official tauri plugin or not, using the appropriate npm package name format

---------

Co-authored-by: Lucas Nogueira <lucas@tauri.app>

.changes/add-community-plugins.md

@@ -0,0 +1,6 @@
+---
+"tauri-cli": patch:bug
+"@tauri-apps/cli": patch:bug
+---
+
+Properly add NPM packages for community plugins when using the `tauri add` command.

crates/tauri-cli/src/add.rs

@@ -49,12 +49,25 @@ pub fn run(options: Options) -> Result<()> {
     .map(|(p, v)| (p, Some(v)))
     .unwrap_or((&options.plugin, None));
 
+  let mut plugins = crate::helpers::plugins::known_plugins();
+  let (metadata, is_known) = plugins
+    .remove(plugin)
+    .map(|metadata| (metadata, true))
+    .unwrap_or_default();
+
   let plugin_snake_case = plugin.replace('-', "_");
   let crate_name = format!("tauri-plugin-{plugin}");
-  let npm_name = format!("@tauri-apps/plugin-{plugin}");
+  let npm_name = if is_known {
+    format!("tauri-apps/plugin-{plugin}")
+  } else {
+    format!("tauri-plugin-{plugin}-api")
+  };
 
-  let mut plugins = crate::helpers::plugins::known_plugins();
-  let metadata = plugins.remove(plugin).unwrap_or_default();
+  if !is_known && (options.tag.is_some() || options.rev.is_some() || options.branch.is_some()) {
+    anyhow::bail!(
+      "Git options --tag, --rev and --branch can only be used with official Tauri plugins"
+    );
+  }
 
   let frontend_dir = resolve_frontend_dir();
   let tauri_dir = tauri_dir();

crates/tauri-cli/src/helpers/plugins.rs

@@ -69,6 +69,7 @@ pub fn known_plugins() -> HashMap<&'static str, PluginMetadata> {
     "shell",
     "upload",
     "websocket",
+    "opener",
   ] {
     plugins.entry(p).or_default();
   }