chore(platform): replace runtime console diagnostics

What changed:
- Replaced platform-service runtime console diagnostics with structured stderr logging helpers.
- Preserved push notification, AI diagnostics, auto-trigger, and diagnostics repository error handling semantics.

Warning impact:
- Platform runtime no-console warnings: 12 -> 0.
- Workspace lint: 12 -> 0 warnings.

Verification:
- pnpm --filter @lysnrai/platform-service build
- pnpm --filter @lysnrai/platform-service test
- pnpm --filter @lysnrai/platform-service exec eslint <runtime files> --ext .ts
- pnpm lint

services/platform-service/src/lib/push-notifications.ts

@@ -32,6 +32,22 @@ interface PushPayload {
   badge?: number;
 }
 
+function logPushWarning(message: string, extra?: Record<string, unknown>): void {
+  process.stderr.write(JSON.stringify({ level: 'warn', module: 'push', message, ...extra }) + '\n');
+}
+
+function logPushError(message: string, error: unknown, extra?: Record<string, unknown>): void {
+  process.stderr.write(
+    JSON.stringify({
+      level: 'error',
+      module: 'push',
+      message,
+      error: error instanceof Error ? error.message : String(error),
+      ...extra,
+    }) + '\n'
+  );
+}
+
 /**
  * Store or update device token for push notifications
  */
@@ -130,7 +146,7 @@ export async function sendFCM(
   // Get FCM server key from environment
   const fcmKey = process.env.FCM_SERVER_KEY;
   if (!fcmKey) {
-    console.warn('[Push] FCM_SERVER_KEY not configured');
+    logPushWarning('FCM_SERVER_KEY not configured');
     return results;
   }
 
@@ -164,11 +180,11 @@ export async function sendFCM(
         results.success.push(token);
       } else {
         const error = await response.text();
-        console.error(`[Push] FCM failed for token ${token.substring(0, 16)}...:`, error);
+        logPushError('FCM send failed', error, { tokenPrefix: token.substring(0, 16) });
         results.failed.push(token);
       }
     } catch (err) {
-      console.error(`[Push] FCM error for token ${token.substring(0, 16)}...:`, err);
+      logPushError('FCM send error', err, { tokenPrefix: token.substring(0, 16) });
       results.failed.push(token);
     }
   }
@@ -194,7 +210,7 @@ export async function sendAPNS(
   const apnsPrivateKey = process.env.APNS_PRIVATE_KEY;
 
   if (!apnsKeyId || !apnsTeamId || !apnsBundleId || !apnsPrivateKey) {
-    console.warn('[Push] APNS credentials not fully configured');
+    logPushWarning('APNS credentials not fully configured');
     return results;
   }
 
@@ -241,7 +257,10 @@ export async function sendAPNS(
         results.success.push(token);
       } else {
         const error = await response.text();
-        console.error(`[Push] APNS failed for token ${token.substring(0, 16)}...:`, error);
+        logPushError('APNS send failed', error, {
+          status: response.status,
+          tokenPrefix: token.substring(0, 16),
+        });
         results.failed.push(token);
 
         // Handle invalid token (410 Gone)
@@ -250,7 +269,7 @@ export async function sendAPNS(
         }
       }
     } catch (err) {
-      console.error(`[Push] APNS error for token ${token.substring(0, 16)}...:`, err);
+      logPushError('APNS send error', err, { tokenPrefix: token.substring(0, 16) });
       results.failed.push(token);
     }
   }

services/platform-service/src/modules/ai-diagnostics/embedding-client.ts

@@ -1,6 +1,5 @@
 /* eslint-disable @typescript-eslint/no-unused-vars */
 import { config } from '../../lib/config.js';
-import type { FastifyBaseLogger } from 'fastify';
 
 // ============================================================================
 // Azure OpenAI Embedding Client
@@ -11,6 +10,17 @@ const EMBEDDING_DIMENSIONS = 1536;
 const MAX_BATCH_SIZE = 100; // Azure OpenAI limit
 const MAX_TOKENS_PER_REQUEST = 8192;
 
+function logEmbeddingError(message: string, error: unknown): void {
+  process.stderr.write(
+    JSON.stringify({
+      level: 'error',
+      module: 'ai-diagnostics.embeddings',
+      message,
+      error: error instanceof Error ? error.message : String(error),
+    }) + '\n'
+  );
+}
+
 interface EmbeddingResponse {
   object: 'list';
   data: Array<{
@@ -93,7 +103,7 @@ export async function generateEmbedding(
       model: data.model,
     };
   } catch (error) {
-    console.error('Failed to generate embedding:', error);
+    logEmbeddingError('Failed to generate embedding', error);
     throw error;
   }
 }
@@ -174,7 +184,7 @@ export async function generateEmbeddingsBatch(
         await new Promise(resolve => setTimeout(resolve, 100));
       }
     } catch (error) {
-      console.error('Failed to generate batch embeddings:', error);
+      logEmbeddingError('Failed to generate batch embeddings', error);
       throw error;
     }
   }

services/platform-service/src/modules/ai-diagnostics/llm-analyzer.ts

@@ -21,6 +21,17 @@ interface RootCauseAnalysisPrompt {
   analysisType: 'root_cause' | 'pattern' | 'comparison' | 'trend';
 }
 
+function logAnalyzerError(message: string, error: unknown): void {
+  process.stderr.write(
+    JSON.stringify({
+      level: 'error',
+      module: 'ai-diagnostics.llm-analyzer',
+      message,
+      error: error instanceof Error ? error.message : String(error),
+    }) + '\n'
+  );
+}
+
 const ROOT_CAUSE_ANALYSIS_PROMPT_TEMPLATE = `You are an expert software engineer diagnosing production errors. Analyze this error cluster and provide root cause insights.
 
 ## Error Cluster
@@ -206,7 +217,7 @@ async function callLLM(
       completionTokens: data.usage?.completion_tokens || 0,
     };
   } catch (error) {
-    console.error('LLM call failed:', error);
+    logAnalyzerError('LLM call failed', error);
     throw error;
   }
 }

services/platform-service/src/modules/diagnostics/auto-triggers.ts

@@ -9,6 +9,17 @@ import type { DebugSessionDoc } from './types.js';
 import { createSession } from './repository.js';
 import { getRegisteredContainer } from '@bytelyst/cosmos';
 
+function logTriggerError(message: string, error: unknown): void {
+  process.stderr.write(
+    JSON.stringify({
+      level: 'error',
+      module: 'diagnostics.auto-triggers',
+      message,
+      error: error instanceof Error ? error.message : String(error),
+    }) + '\n'
+  );
+}
+
 // ─────────────────────────────────────────────────────────────────────────────
 // Trigger Configuration Types
 // ─────────────────────────────────────────────────────────────────────────────
@@ -399,7 +410,7 @@ async function sendTriggerNotifications(
       });
     } catch (err) {
       // Log but don't fail
-      console.error('Failed to send Slack notification:', err);
+      logTriggerError('Failed to send Slack notification', err);
     }
   }
 
@@ -427,7 +438,7 @@ async function sendTriggerNotifications(
         }),
       });
     } catch (err) {
-      console.error('Failed to send Teams notification:', err);
+      logTriggerError('Failed to send Teams notification', err);
     }
   }
 

services/platform-service/src/modules/diagnostics/repository.ts

@@ -39,6 +39,12 @@ function screenshotsCollection() {
   return getCollection<DebugScreenshotDoc>('debug_screenshots', '/sessionId');
 }
 
+function logDiagnosticsWarning(message: string, extra?: Record<string, unknown>): void {
+  process.stderr.write(
+    JSON.stringify({ level: 'warn', module: 'diagnostics.repository', message, ...extra }) + '\n'
+  );
+}
+
 // ─────────────────────────────────────────────────────────────────────────────
 // Helper: Build composite partition key
 // ─────────────────────────────────────────────────────────────────────────────
@@ -320,9 +326,10 @@ export async function updateSessionStats(
       retries++;
       if (retries >= MAX_RETRIES) {
         // Log warning but don't fail the ingest - data integrity > stats accuracy
-        console.warn(
-          `[diagnostics] Failed to update session stats after ${MAX_RETRIES} retries for session ${sessionId}`
-        );
+        logDiagnosticsWarning('Failed to update session stats after max retries', {
+          retries: MAX_RETRIES,
+          sessionId,
+        });
         return;
       }
       // Small delay before retry