fix: resolve bug_bash UX/logging issues (#1054 #1055 #1058) (#1072)

* fix(web,db): improve auth UX + reduce naive timestamp log noise

* fix(clippy): keep memory test modules at end of file

src/db/libsql/mod.rs

@@ -16,6 +16,7 @@ mod workspace;
 
 use std::path::Path;
 use std::sync::Arc;
+use std::sync::atomic::{AtomicBool, Ordering};
 
 use async_trait::async_trait;
 use chrono::{DateTime, NaiveDateTime, Utc};
@@ -32,6 +33,8 @@ use crate::workspace::MemoryDocument;
 
 use crate::db::libsql_migrations;
 
+static NAIVE_TIMESTAMP_LOGGED: AtomicBool = AtomicBool::new(false);
+
 /// Explicit column list for routines table (matches positional access in `row_to_routine_libsql`).
 pub(crate) const ROUTINE_COLUMNS: &str = "\
     id, name, description, user_id, enabled, \
@@ -163,24 +166,27 @@ impl LibSqlBackend {
 ///
 /// Returns an error if none of the formats match.
 pub(crate) fn parse_timestamp(s: &str) -> Result<DateTime<Utc>, String> {
+    let log_naive_timestamp_once = || {
+        if !NAIVE_TIMESTAMP_LOGGED.swap(true, Ordering::Relaxed) {
+            tracing::debug!(
+                timestamp = %s,
+                "parsed naive timestamp without timezone; assuming UTC for backward compatibility"
+            );
+        }
+    };
+
     // RFC 3339 (our canonical write format)
     if let Ok(dt) = DateTime::parse_from_rfc3339(s) {
         return Ok(dt.with_timezone(&Utc));
     }
     // Naive with fractional seconds (legacy or SQLite datetime() output)
     if let Ok(ndt) = NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S%.f") {
-        tracing::debug!(
-            timestamp = %s,
-            "parsed naive timestamp without timezone; assuming UTC for backward compatibility"
-        );
+        log_naive_timestamp_once();
         return Ok(ndt.and_utc());
     }
     // Naive without fractional seconds (legacy format)
     if let Ok(ndt) = NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S") {
-        tracing::debug!(
-            timestamp = %s,
-            "parsed naive timestamp without timezone; assuming UTC for backward compatibility"
-        );
+        log_naive_timestamp_once();
         return Ok(ndt.and_utc());
     }
     Err(format!("unparseable timestamp: {:?}", s))