fix(rust-bridge): correct Email.addHeader() calls and IBounceDetection interface

Use addHeader() instead of non-existent setHeader() for security
result headers, and align IBounceDetection with actual Rust struct
fields (bounce_type + category only).

ts/mail/routing/classes.unified.email.server.ts

@@ -656,12 +656,12 @@ export class UnifiedEmailServer extends EventEmitter {
         const dkimSummary = result.dkim
           .map(d => `${d.status}${d.domain ? ` (${d.domain})` : ''}`)
           .join(', ');
-        email.setHeader('X-DKIM-Result', dkimSummary);
+        email.addHeader('X-DKIM-Result', dkimSummary);
       }
 
       // Apply SPF result header
       if (result.spf) {
-        email.setHeader('Received-SPF', `${result.spf.result} (domain: ${result.spf.domain}, ip: ${result.spf.ip})`);
+        email.addHeader('Received-SPF', `${result.spf.result} (domain: ${result.spf.domain}, ip: ${result.spf.ip})`);
 
         // Mark as spam on SPF hard fail
         if (result.spf.result === 'fail') {
@@ -672,7 +672,7 @@ export class UnifiedEmailServer extends EventEmitter {
 
       // Apply DMARC result header and policy
       if (result.dmarc) {
-        email.setHeader('X-DMARC-Result', `${result.dmarc.action} (policy=${result.dmarc.policy}, dkim=${result.dmarc.dkim_result}, spf=${result.dmarc.spf_result})`);
+        email.addHeader('X-DMARC-Result', `${result.dmarc.action} (policy=${result.dmarc.policy}, dkim=${result.dmarc.dkim_result}, spf=${result.dmarc.spf_result})`);
 
         if (result.dmarc.action === 'reject') {
           email.mightBeSpam = true;

ts/security/classes.rustsecuritybridge.ts

@@ -46,11 +46,7 @@ interface IValidationResult {
 
 interface IBounceDetection {
   bounce_type: string;
-  severity: string;
   category: string;
-  should_retry: boolean;
-  recommended_action: string;
-  details: string;
 }
 
 interface IReputationResult {