Remove legal check fallback to fix 60s H2 stream idle timeout

With timeout=45s + fallback timeout=30s, the total silence was 75s,
exceeding the 60s H2 idle stream limit in the browser. Remove the
fallback: if dbn-legal-agent-v3 times out or fails, return empty
immediately. Legal check is non-critical (wrapped in try/catch in
generate()); the draft is still correct without it.

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

includes/bootstrap.php

@@ -966,23 +966,7 @@ function dbnToolsRunLegalCheck(string $brief, string $docType): array
         );
         $text = trim((string)($response['choices'][0]['message']['content'] ?? ''));
     } catch (Throwable $e) {
-        // v3 unavailable — fall back to qwen2.5:7b as safety net
-    }
-
-    // Fallback: if v3 timed out or returned empty, retry with qwen2.5:7b
-    if (empty($text) || str_word_count($text) < 8) {
-        try {
-            $fallback = dbnToolsCallGpuLlm(
-                [
-                    ['role' => 'system', 'content' => $sysMsg],
-                    ['role' => 'user', 'content' => $question],
-                ],
-                array_merge($opts, ['model' => 'qwen2.5:7b', 'timeout' => 30])
-            );
-            $text = trim((string)($fallback['choices'][0]['message']['content'] ?? ''));
-        } catch (Throwable $e) {
-            return [];
-        }
+        return []; // v3 timed out or unavailable — skip legal check (non-critical)
     }
 
     if (empty($text) || str_word_count($text) < 15) {