COL-BOT-02: guard the honeypot, log failed bans, stop log_embed panicking

The honeypot banned whoever posted, unconditionally. Add guards so it never
bans a bot, a webhook, the bot itself, or anyone who can moderate
(ban_members / manage_messages / administrator, computed from the cached guild).
A failed ban now logs the user and error instead of being silent.

Remove the .expect("LOG FAIL") in log_embed: it runs inside a message handler,
so a transient Discord failure was a panic; it now eprintln!s and returns.

Decouple on_message so honeypot and the LeetCode thread each run and log
independently — a failure in one no longer skips the other, and neither
propagates out of the event handler.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017XrE7F9ZuBWdQnS8CZvYDE

src/commands/mods_only.rs

@@ -62,8 +62,11 @@ pub async fn log_embed(
     // Send the embed (logs_channel_id is parsed once at boot; see AppState).
     let builder = serenity::CreateMessage::new().embed(embed);
 
-    let send_log = logs_channel_id.send_message(ctx, builder).await;
-    send_log.expect("LOG FAIL");
+    // Do NOT .expect() here: this runs inside a message handler, and a panic on a
+    // transient Discord failure takes the whole handler down for that message.
+    if let Err(err) = logs_channel_id.send_message(ctx, builder).await {
+        eprintln!("[log_embed] failed to write to logs channel: {err}");
+    }
 
     Ok(())
 }

src/events/message.rs

@@ -12,6 +12,33 @@ async fn honeypot(
 
     if honeypot_channel_id.eq(current_channel_id) {
         let user = &new_message.author;
+
+        // Never ban a bot, a webhook, or ourselves. The honeypot exists to catch
+        // spam accounts; banning another club integration (or the bot itself)
+        // because it posted in the wrong channel is a self-inflicted outage.
+        if user.bot || new_message.webhook_id.is_some() || user.id == ctx.cache.current_user().id {
+            return Ok(());
+        }
+
+        // Never ban someone who can moderate. A moderator checking whether the
+        // honeypot works should not be the person it catches. This reads the
+        // cached guild; if it is unavailable we fall through and let the honeypot
+        // act, rather than skipping the check silently for everyone.
+        if let Some(guild_id) = new_message.guild_id
+            && let Ok(member) = guild_id.member(ctx, user.id).await
+        {
+            // Guild-level moderator identity is exactly what we want here; the
+            // deprecation is about per-channel permission overwrites, which are
+            // irrelevant to "can this person moderate at all".
+            #[allow(deprecated)]
+            let perms = member.permissions(ctx);
+            if let Ok(perms) = perms
+                && (perms.ban_members() || perms.manage_messages() || perms.administrator())
+            {
+                return Ok(());
+            }
+        }
+
         let username = &user.name;
         let user_id = &user.id;
         let avatar_url = user.avatar_url();
@@ -21,7 +48,8 @@ async fn honeypot(
             .ban_with_reason(ctx, user_id, 2, "Message sent in honeypot channel.")
             .await;
 
-        if ban_user.is_ok() {
+        match ban_user {
+            Ok(()) => {
                 log_embed(
                     ctx,
                     data.state.logs_channel_id,
@@ -36,6 +64,13 @@ async fn honeypot(
                 )
                 .await?;
             }
+            // A honeypot that cannot ban is information the mods need.
+            Err(err) => {
+                eprintln!(
+                    "[honeypot] failed to ban {username} ({user_id}) in the honeypot channel: {err}"
+                );
+            }
+        }
     }
 
     Ok(())
@@ -84,7 +119,14 @@ pub async fn on_message(
     new_message: &serenity::Message,
     data: &Data,
 ) -> Result<(), Error> {
-    honeypot(ctx, new_message, data).await?;
-    create_leetcode_thread(ctx, new_message, data).await?;
+    // Independent features. A failure in one must not skip the other, and neither
+    // should propagate out of the event handler, where the default on_error only
+    // eprintln!s (OPS-04).
+    if let Err(err) = honeypot(ctx, new_message, data).await {
+        eprintln!("[on_message] honeypot failed: {err}");
+    }
+    if let Err(err) = create_leetcode_thread(ctx, new_message, data).await {
+        eprintln!("[on_message] leetcode thread failed: {err}");
+    }
     Ok(())
 }