feat: Update Add command to use --tag flag and sort tags alphabetically

src/main.rs

@@ -38,10 +38,9 @@ enum Commands {
     /// Add tags to files
     Add {
         /// Tags to add
-        #[arg(required = true)]
+        #[arg(long = "tag", required = true)]
         tags: Vec<String>,
         /// Files to process
-        #[arg(required = true)]
         files: Vec<String>,
     },
 }

src/tag_engine.rs

@@ -65,13 +65,26 @@ pub fn parse_tags(filename: &str) -> Result<(String, Vec<String>, String), Parse
             }
         }
         
-        let mut unique_tags = std::collections::HashSet::new();
-        for tag in tag_part.split_whitespace() {
-            validate_tag(tag)?;
-            unique_tags.insert(tag.to_string());
-        }
-        
-        unique_tags.into_iter().collect()
+        // First parse all tags
+        let parsed_tags: Vec<String> = tag_part
+            .split_whitespace()
+            .map(|tag| {
+                validate_tag(tag)?;
+                Ok(tag.to_string())
+            })
+            .collect::<Result<_, TagError>>()?;
+
+        // Then filter duplicates using a HashSet
+        let unique_tags: Vec<String> = parsed_tags
+            .into_iter()
+            .collect::<std::collections::HashSet<_>>()
+            .into_iter()
+            .collect();
+
+        // Finally sort
+        let mut tags = unique_tags;
+        tags.sort();
+        tags
     } else {
         Vec::new()
     };