feat: declare MultiFlexi events (schema 3.4.0) in app definitions

Add events.emits/consumes blocks and bump schemaVersion to 3.4.0 so
Node-RED can connect producing and consuming MultiFlexi processes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: Vitexus

multiflexi/abraflexi-reminder.multiflexi.app.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://raw.githubusercontent.com/VitexSoftware/php-vitexsoftware-multiflexi-core/refs/heads/main/multiflexi.app.schema.json",
-  "schemaVersion": "3.1.0",
+  "schemaVersion": "3.4.0",
   "uuid": "0fd52fdd-1c83-4346-b9f9-13e82bd5d6d0",
   "name": {
     "en": "Reminder",
@@ -21,6 +21,13 @@
   ],
   "homepage": "https://github.com/VitexSoftware/abraflexi-reminder",
   "executable": "abraflexi-reminder",
+  "events": {
+    "emits": {
+      "invoice.reminder.sent": {
+        "description": "An overdue payment reminder was sent"
+      }
+    }
+  },
   "environment": {
     "DEBUG": {
       "type": "bool",

multiflexi/clear_reminder_labels.multiflexi.app.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://raw.githubusercontent.com/VitexSoftware/php-vitexsoftware-multiflexi-core/refs/heads/main/multiflexi.app.schema.json",
-  "schemaVersion": "3.1.0",
+  "schemaVersion": "3.4.0",
   "uuid": "138f1310-8e76-4670-bc55-47a3400795e1",
   "name": {
     "en": "Clear Reminder Labels",
@@ -20,6 +20,13 @@
   ],
   "homepage": "https://github.com/VitexSoftware/abraflexi-reminder",
   "executable": "abraflexi-reminder-clean-labels",
+  "events": {
+    "emits": {
+      "reminder.labels.cleared": {
+        "description": "Reminder labels were cleared"
+      }
+    }
+  },
   "environment": {
     "LANG": {
       "type": "set",

multiflexi/debts_overview.multiflexi.app.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://raw.githubusercontent.com/VitexSoftware/php-vitexsoftware-multiflexi-core/refs/heads/main/multiflexi.app.schema.json",
-  "schemaVersion": "3.0.0",
+  "schemaVersion": "3.4.0",
   "uuid": "82710b78-5cf9-4380-a7e2-62b6e65b2027",
   "name": {
     "en": "Debts overview",
@@ -21,6 +21,13 @@
   ],
   "homepage": "https://github.com/VitexSoftware/abraflexi-reminder",
   "executable": "abraflexi-show-debts",
+  "events": {
+    "emits": {
+      "debts.reported": {
+        "description": "Outstanding debts were reported"
+      }
+    }
+  },
   "environment": {
     "ABRAFLEXI_COMPANY": {
       "type": "string",

multiflexi/inventarize.multiflexi.app.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://raw.githubusercontent.com/VitexSoftware/php-vitexsoftware-multiflexi-core/refs/heads/main/multiflexi.app.schema.json",
-  "schemaVersion": "3.0.0",
+  "schemaVersion": "3.4.0",
   "uuid": "2d08b097-6da2-475d-b5cc-85f51cf5e463",
   "name": {
     "en": "Notify Customers",
@@ -21,6 +21,13 @@
   ],
   "homepage": "https://github.com/VitexSoftware/abraflexi-reminder",
   "executable": "abraflexi-notify-customers",
+  "events": {
+    "emits": {
+      "customer.notified": {
+        "description": "Customers were notified"
+      }
+    }
+  },
   "environment": {
     "ABRAFLEXI_COMPANY": {
       "type": "string",