refactor(render,codegen-spring): FR-010 Plan 3 clarity cleanup (no behavior change)

- OutputFormatRenderer: extract resolveInstruction(field, overrides) helper to
  eliminate the two-line override-then-field-default pattern duplicated between
  inlineContent() and renderGuide().
- OutputFormatSpecEmitter: simplify resolvePromptStyleEnum by using
  OutputTemplate.getPromptStyle() (which already normalises the attr read +
  null-default) instead of double hasMetaAttr/getMetaAttr lookup + manual null
  check; adds OutputTemplate import.
- Verify.checkOutputPrompt: move requiredFieldNames null-guard above haystack
  init so the early-return fires before the defensive string copy.

render 211/211 · codegen-spring 71/71 — no assertions weakened.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: dmealing

server/java/codegen-spring/src/main/java/com/metaobjects/generator/spring/OutputFormatSpecEmitter.java

@@ -10,6 +10,7 @@
 import com.metaobjects.field.StringField;
 import com.metaobjects.object.MetaObject;
 import com.metaobjects.template.MetaTemplate;
+import com.metaobjects.template.OutputTemplate;
 import com.metaobjects.template.TemplateConstants;
 
 import java.util.ArrayList;
@@ -97,12 +98,8 @@ private static String resolveFormatEnum(MetaTemplate template) {
      * Default (absent or unrecognized) → {@code PromptStyle.GUIDE}.
      */
     private static String resolvePromptStyleEnum(MetaTemplate template) {
-        String raw = null;
-        if (template.hasMetaAttr(TemplateConstants.ATTR_PROMPT_STYLE, false)) {
-            raw = template.getMetaAttr(TemplateConstants.ATTR_PROMPT_STYLE, false).getValueAsString();
-        }
-        if (raw == null) return "PromptStyle.GUIDE";
-        return switch (raw) {
+        String raw = (template instanceof OutputTemplate ot) ? ot.getPromptStyle() : null;
+        return switch (raw != null ? raw : TemplateConstants.PROMPT_STYLE_DEFAULT) {
             case TemplateConstants.PROMPT_STYLE_INLINE       -> "PromptStyle.INLINE";
             case TemplateConstants.PROMPT_STYLE_EXAMPLE_ONLY -> "PromptStyle.EXAMPLE_ONLY";
             default                                          -> "PromptStyle.GUIDE";

server/java/render/src/main/java/com/metaobjects/render/Verify.java

@@ -55,8 +55,8 @@ private Verify() {}
      */
     public static List<VerifyError> checkOutputPrompt(String fragment, List<String> requiredFieldNames) {
         List<VerifyError> errors = new ArrayList<>();
-        String haystack = fragment == null ? "" : fragment;
         if (requiredFieldNames == null) return errors;
+        String haystack = fragment == null ? "" : fragment;
         for (String name : requiredFieldNames) {
             if (!haystack.contains(name)) {
                 errors.add(new VerifyError(ERR_OUTPUT_PROMPT_FIELD_MISSING, name));

server/java/render/src/main/java/com/metaobjects/render/prompt/OutputFormatRenderer.java

@@ -71,22 +71,26 @@ private static String inlineContent(PromptField field, PromptOverrides overrides
         if (field.kind() == FieldKind.BOOLEAN) {
             return "true | false";
         }
-        String instruction = overrides.instructions().get(field.name());
-        if (instruction == null) instruction = field.instruction();
+        String instruction = resolveInstruction(field, overrides);
         if (instruction != null) {
             return "{" + instruction + "}";
         }
         return "{" + field.name() + "}";
     }
 
+    /** Returns the effective instruction: override first, then field default, or {@code null}. */
+    private static String resolveInstruction(PromptField field, PromptOverrides overrides) {
+        String instruction = overrides.instructions().get(field.name());
+        return instruction != null ? instruction : field.instruction();
+    }
+
     private static String renderGuide(OutputFormatSpec spec, PromptOverrides overrides) {
         StringBuilder sb = new StringBuilder();
         sb.append("Fill in each field as described below:\n");
         for (PromptField field : spec.fields()) {
             String req = field.required() ? "required" : "optional";
             sb.append("- ").append(field.name()).append(" (").append(req).append(")");
-            String instruction = overrides.instructions().get(field.name());
-            if (instruction == null) instruction = field.instruction();
+            String instruction = resolveInstruction(field, overrides);
             if (instruction != null) {
                 sb.append(": ").append(instruction);
             }