Fix rand breaking changes

src/data/totp_key.rs

@@ -21,7 +21,7 @@ pub struct TotpKey {
 impl TotpKey {
     /// Generate a new TOTP key
     pub fn new_random() -> Self {
-        let random_bytes = rand::thread_rng().gen::<[u8; 20]>();
+        let random_bytes = rand::rng().random::<[u8; 20]>();
         Self {
             encoded: base32::encode(BASE32_ALPHABET, &random_bytes),
         }

src/utils/string_utils.rs

@@ -1,14 +1,9 @@
 use lazy_regex::regex_find;
-use rand::distributions::Alphanumeric;
-use rand::Rng;
+use rand::distr::{Alphanumeric, SampleString};
 
 /// Generate a random string of a given size
 pub fn rand_str(len: usize) -> String {
-    rand::thread_rng()
-        .sample_iter(&Alphanumeric)
-        .map(char::from)
-        .take(len)
-        .collect()
+    Alphanumeric.sample_string(&mut rand::rng(), len)
 }
 
 /// Parse environment variables