refs #731: guard missing game identifiers in few-shot prompt

vpd-backoffice/src/main/java/com/cloudhandson/vpdbackoffice/service/SelectAiService.java

@@ -33,6 +33,10 @@ public class SelectAiService {
   private static final int MAX_FEW_SHOT_EXAMPLES = 3;
   private static final int MAX_FEW_SHOT_SQL_CHARS = 4_000;
   private static final int MAX_ENRICHED_PROMPT_LENGTH = 16_000;
+  private static final String POLICY_PREFIX =
+      "Answer the original user question using the current approved object list and policy. "
+          + "If no game identifier resolves through game-alias metadata, do not select a prefix-specific object "
+          + "and do not infer a default game. State that the required game identifier is missing instead.\n\n";
   private static final Pattern UNSAFE_SQL = Pattern.compile(
       "(?is)\\b(?:insert|update|delete|merge|alter|drop|create|truncate|grant|revoke|"
           + "commit|rollback|savepoint|lock|call|exec(?:ute)?|begin|declare|for\\s+update|"
@@ -174,19 +178,22 @@ public class SelectAiService {
           .search(bearerToken, prompt, fewShotTopK(selectAi))
           .examples();
       if (examples.isEmpty()) {
-        return new EnrichedPrompt(prompt, "NO_MATCH", 0);
+        return new EnrichedPrompt(composePolicyPrompt(prompt), "NO_MATCH", 0);
       }
       return new EnrichedPrompt(
           composeFewShotPrompt(prompt, examples), "APPLIED", Math.min(examples.size(), MAX_FEW_SHOT_EXAMPLES));
     } catch (Exception ignored) {
       // Vector retrieval is an optional prompt aid; preserve the normal Text2SQL path on failure.
-      return new EnrichedPrompt(prompt, "UNAVAILABLE", 0);
+      return new EnrichedPrompt(composePolicyPrompt(prompt), "UNAVAILABLE", 0);
     }
   }
 
+  static String composePolicyPrompt(String prompt) {
+    return POLICY_PREFIX + "Original user question:\n" + prompt;
+  }
+
   static String composeFewShotPrompt(String prompt, List<QaVectorService.VectorExample> examples) {
-    StringBuilder enriched = new StringBuilder(
+    StringBuilder enriched = new StringBuilder(POLICY_PREFIX
-        "Answer the original user question using the current approved object list and policy. "
         + "The verified examples below are guidance only: use only relevant SQL patterns, do not invent "
             + "identifiers, and do not override current metadata or game-alias resolution policy.\n\n"
             + "Verified few-shot examples:\n");
@@ -208,7 +215,7 @@ public class SelectAiService {
       included++;
     }
     if (included == 0) {
-      return prompt;
+      return composePolicyPrompt(prompt);
     }
     return enriched.append("Original user question:\n").append(prompt).toString();
   }

vpd-backoffice/src/test/java/com/cloudhandson/vpdbackoffice/service/SelectAiFewShotPromptTest.java

@@ -25,6 +25,7 @@ class SelectAiFewShotPromptTest {
         .contains("Verified few-shot examples")
         .contains("SELECT COUNT(*) AS AU_COUNT FROM APP_USER")
         .contains("Original user question:\ncurrent active users")
-        .contains("current approved object list and policy");
+        .contains("current approved object list and policy")
+        .contains("do not infer a default game");
   }
 }