feat(i18n): Make i18n default feature and always use embedded assets

- Add i18n to default features in Cargo.toml
- Modify I18nBundle::load() to always use embedded assets when i18n feature is enabled
- Remove confusing warning about "locales directory not found"
- Locales are now embedded via rust-embed by default

Fixes issue where translations showed placeholders like [nav-chat] instead of actual text.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Cargo.toml

@@ -10,9 +10,9 @@ keywords = ["bot", "chatbot", "ai", "conversational", "library"]
 categories = ["api-bindings", "web-programming"]
 
 [features]
-default = []
+default = ["database", "i18n"]
 full = ["database", "http-client", "validation", "resilience", "i18n"]
-database = []
+database = ["i18n"]
 http-client = ["dep:reqwest"]
 validation = []
 resilience = []

src/i18n/bundle.rs

@@ -173,18 +173,21 @@ pub struct I18nBundle {
 
 impl I18nBundle {
     pub fn load(base_path: &str) -> BotResult<Self> {
+        // When i18n feature is enabled, locales are ALWAYS embedded via rust-embed
+        // Filesystem loading is deprecated - use embedded assets only
+        #[cfg(feature = "i18n")]
+        {
+            log::info!("Loading embedded locale translations (rust-embed)");
+            return Self::load_embedded();
+        }
+
+        #[cfg(not(feature = "i18n"))]
+        {
+            let _base_path = base_path; // Suppress unused warning when i18n is enabled
+
             let base = Path::new(base_path);
 
             if !base.exists() {
-            #[cfg(feature = "i18n")]
-            {
-                log::info!(
-                    "Locales directory not found at {}, trying embedded assets",
-                    base_path
-                );
-                return Self::load_embedded();
-            }
-            #[cfg(not(feature = "i18n"))]
                 return Err(BotError::config(format!(
                     "locales directory not found: {base_path}"
                 )));
@@ -223,6 +226,7 @@ impl I18nBundle {
                 fallback,
             })
         }
+    }
 
     #[cfg(feature = "i18n")]
     fn load_embedded() -> BotResult<Self> {