fix: Fix OsRng import and refactor Redis connection setup

- Fix password-hash version mismatch (0.6→0.5) causing OsRng to be
  gated behind missing getrandom feature; enable argon2 rand feature
- Extract get_redis_connection() helper to deduplicate Redis client
  setup across authentication, repo control, and tests
- Tighten username validation regex to require ≥2 chars and disallow
  leading/trailing dots or hyphens
- Handle malformed cookies without split_once gracefully (continue
  instead of panic)
- Fix typos: "rated commands" → "related commands" in CLI help text

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>
Signed-off-by: KunoiSayami <[email protected]>

1 files changed, 6 insertions, 4 deletions

diff --git a/src/test.rs b/src/test.rs
index 7628921..e71aee4 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -55,8 +55,9 @@ mod core {
     }
 
     async fn async_test_redis() -> anyhow::Result<()> {
-        let redis_conn = redis::Client::open(crate::datastructures::DEFAULT_REDIS_URL)?;
-        let mut conn = redis_conn.get_multiplexed_async_connection().await?;
+        let mut conn =
+            crate::datastructures::get_redis_connection(crate::datastructures::DEFAULT_REDIS_URL)
+                .await?;
 
         let s = rand_str(crate::datastructures::COOKIE_LENGTH);
         conn.set_ex::<_, _, String>("auth_test", &s, 60).await?;
@@ -344,8 +345,9 @@ mod core {
     }
 
     async fn clear_redis_setting() -> anyhow::Result<()> {
-        let client = redis::Client::open(crate::datastructures::DEFAULT_REDIS_URL)?;
-        let mut conn = client.get_multiplexed_async_connection().await?;
+        let mut conn =
+            crate::datastructures::get_redis_connection(crate::datastructures::DEFAULT_REDIS_URL)
+                .await?;
 
         for key in &[
             "cgit_repo_test",