fix: add X-WS-* header detection and attachment test

- Detect X-WS-* headers (e.g., X-WS-Attachment-UUID) as MIME headers
  to ensure attachment headers like Content-Type and Content-Disposition
  get normalized properly
- Add test case for attachment header normalization
- Bump version to 0.5.0

The normalization fixes malformed continuation lines in attachment
headers generated by Infomaniak webmail, where lines like
"name=file.pdf" are missing the required leading whitespace.

Cargo.lock

@@ -597,7 +597,7 @@ dependencies = [
 
 [[package]]
 name = "rs_pop_imap_importer"
-version = "0.3.0"
+version = "0.5.0"
 dependencies = [
  "clap",
  "dotenvy",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rs_pop_imap_importer"
-version = "0.3.0"
+version = "0.5.0"
 edition = "2024"
 
 [lib]

src/email_processor.rs

@@ -136,7 +136,7 @@ pub fn normalize_headers(email: &str) -> Result<String, Box<dyn Error>> {
                     header_count += 1;
                     last_was_header = true;
                     // Check for typical MIME headers
-                    if line.starts_with("Content-") || line.starts_with("MIME-Version") {
+                    if line.starts_with("Content-") || line.starts_with("MIME-Version") || line.starts_with("X-WS-") {
                         has_mime_headers = true;
                     }
                 } else if is_continuation || last_was_header {
@@ -234,4 +234,26 @@ mod tests {
         let result = normalize_headers(email).unwrap();
         assert_eq!(email, result, "Email should not be modified if already compliant");
     }
+
+    #[test]
+    fn test_normalize_attachment_headers() {
+        let email = concat!(
+            "From: test@example.com\r\n",
+            "Subject: Test\r\n",
+            "\r\n",
+            "--boundary\r\n",
+            "X-WS-Attachment-UUID: 123\r\n",
+            "Content-Type: application/pdf;\r\n",
+            "name=test.pdf\r\n",
+            "Content-Disposition: attachment;\r\n",
+            "filename=test.pdf\r\n",
+            "\r\n",
+            "data"
+        );
+        let result = normalize_headers(email).unwrap();
+        assert!(result.contains("Content-Type: application/pdf;\r\n name=test.pdf"),
+                "Should add space to Content-Type continuation");
+        assert!(result.contains("Content-Disposition: attachment;\r\n filename=test.pdf"),
+                "Should add space to Content-Disposition continuation");
+    }
 }