fix: Ai review fixes — quit-race, token overflow, comment + nits

- Guard conversations.remember() on asker==null: a PlayerQuitEvent
  forgets the history (carry-forward #6), and re-adding here after the
  quit would resurrect it. lastAnswer stays regardless so /ia corrigir
  can still correct the last answer.
- Saturate the retry token ceiling: max_tokens near Integer.MAX_VALUE
  would overflow to a negative budget sent to the API.
- Tighten the constructor comment: aiUrl/aiWikiChars/aiMemoryExchanges/
  aiMemoryMinutes are baked; everything else (aiProfile, aiModel,
  aiMaxTokens, aiTemperature, aiInstructions, aiServerContext) is read
  live, not just aiProfile.
- Drop unused import java.util.List; add trailing newline.

src/main/java/dev/marcospaulo/canalhandia/Ai.java

@@ -11,7 +11,6 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.time.LocalDate;
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 import java.util.UUID;
 
@@ -89,9 +88,12 @@ final class Ai {
         this.conversations = new Conversations(settings.aiMemoryExchanges(), settings.aiMemoryMinutes());
         this.corrections = new Corrections(new java.io.File(plugin.getDataFolder(), "correcoes.yml"));
         // Note: aiUrl(), aiWikiChars(), aiMemoryExchanges() and aiMemoryMinutes()
-        // are baked here at construction. Only aiProfile() is read live in the
-        // async body, which is correct — operators switch profiles live without
-        // a restart, and the other settings are not meant to be hot-swapped.
+        // are baked here at construction (passed to the MiniMax/Wiki/Conversations
+        // constructors and not re-read). Everything else — aiProfile(), aiModel(),
+        // aiMaxTokens(), aiTemperature(), aiInstructions(), aiServerContext() — is
+        // read live in the async body, so operators can hot-swap them. Profiles in
+        // particular switch live without a restart; the baked four are not meant
+        // to be hot-swapped.
     }
 
     /** True if a key is configured. Without one the module stays quiet. */
@@ -247,8 +249,11 @@ final class Ai {
                 // occasionally drops a foreign word mid-sentence. Both are
                 // worth one retry before giving up (carry-forwards #3 and #7).
                 if (answer == null || AiText.hasForeignScript(answer)) {
-                    answer = api.answer(key, settings.aiModel(), messages,
-                            settings.aiMaxTokens() * 2, 0.1);
+                    // Cap before doubling: an absurd ia.max-tokens near
+                    // Integer.MAX_VALUE would overflow to a negative budget
+                    // and be sent to the API. The default (1200) is unaffected.
+                    int retryTokens = Math.min(settings.aiMaxTokens(), Integer.MAX_VALUE / 2) * 2;
+                    answer = api.answer(key, settings.aiModel(), messages, retryTokens, 0.1);
                 }
                 if (answer != null && AiText.hasForeignScript(answer)) {
                     plugin.getLogger().warning("Resposta descartada por idioma estrangeiro.");
@@ -317,7 +322,13 @@ final class Ai {
             return;
         }
         String clean = AiText.sanitise(answer, settings.aiMaxAnswer());
+        // Only remember if the asker is still online: a PlayerQuitEvent forgets
+        // the player's history (carry-forward #6), and re-adding here after the
+        // quit would resurrect it. lastAnswer stays regardless, so /ia corrigir
+        // can still correct the last answer even after the asker left.
+        if (asker != null) {
             conversations.remember(askerId, question, clean);
+        }
         lastAnswer = new Answered(askerId, question, clean);
 
         Component message = Msg.tag("IA", NamedTextColor.LIGHT_PURPLE)