Make custom Tags relation filterable on all four entities

Expose the custom many-to-many CTag "Tags" relation as a linkMultiple
field (cTags) so it can be added to the list-view Search Filters, and
build the full Tags setup on Lead from scratch in parity with the others.

Opportunity / Contact / Account (relation already existed):
- add fields.cTags (linkMultiple) to entityDefs
- add cTags to the Search-Filters layout (Opportunity appended, preserving
  cAccount1; Contact/Account get a full filters.json incl. cTags)

Lead (built from scratch):
- create Lead<->CTag many-to-many relation via EntityManager (relationName
  cLeadTag, join table c_lead_tag); link normalized to cTags to mirror the
  other three (API auto-prefix had produced cCTags)
- add cTags field, de_DE/en_US labels, clientDefs panel polish (create:false,
  unlink-only row actions), bottomPanelsDetail entry, and filters.json
- CTag side: links.interessenten label de "Interessenten" / en "Leads"

Verified via API/DB: cTags linkMultiple present on all four scopes; Lead
link/CTag.interessenten resolve; Any of / All of / None of filters execute
and return correct results end-to-end; existing data intact.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

espocrm-custom/custom/Espo/Custom/Resources/i18n/de_DE/CTag.json

@@ -5,11 +5,13 @@
   "fields": {
     "verkaufschancen": "Verkaufschancen",
     "kontakte": "Kontakte",
-        "firmen": "Firmen"
+    "firmen": "Firmen",
+    "interessenten": "Interessenten"
   },
   "links": {
     "verkaufschancen": "Verkaufschancen",
     "kontakte": "Kontakte",
-        "firmen": "Firmen"
+    "firmen": "Firmen",
+    "interessenten": "Interessenten"
   }
 }

espocrm-custom/custom/Espo/Custom/Resources/i18n/de_DE/Lead.json

@@ -0,0 +1,8 @@
+{
+  "fields": {
+    "cTags": "Tags"
+  },
+  "links": {
+    "cTags": "Tags"
+  }
+}

espocrm-custom/custom/Espo/Custom/Resources/i18n/en_US/CTag.json

@@ -5,11 +5,13 @@
   "fields": {
     "verkaufschancen": "Verkaufschancen",
     "kontakte": "Kontakte",
-        "firmen": "Firmen"
+    "firmen": "Firmen",
+    "interessenten": "Leads"
   },
   "links": {
     "verkaufschancen": "Verkaufschancen",
     "kontakte": "Kontakte",
-        "firmen": "Firmen"
+    "firmen": "Firmen",
+    "interessenten": "Leads"
   }
 }

espocrm-custom/custom/Espo/Custom/Resources/i18n/en_US/Lead.json

@@ -0,0 +1,8 @@
+{
+  "fields": {
+    "cTags": "Tags"
+  },
+  "links": {
+    "cTags": "Tags"
+  }
+}

espocrm-custom/custom/Espo/Custom/Resources/layouts/Account/filters.json

@@ -0,0 +1,20 @@
+[
+  "assignedUser",
+  "teams",
+  "createdAt",
+  "createdBy",
+  "modifiedAt",
+  "streamUpdatedAt",
+  "type",
+  "industry",
+  "description",
+  "emailAddress",
+  "phoneNumber",
+  "targetLists",
+  "billingAddressCountry",
+  "billingAddress",
+  "shippingAddress",
+  "website",
+  "campaign",
+  "cTags"
+]

espocrm-custom/custom/Espo/Custom/Resources/layouts/Contact/filters.json

@@ -0,0 +1,16 @@
+[
+  "assignedUser",
+  "teams",
+  "createdAt",
+  "createdBy",
+  "modifiedAt",
+  "streamUpdatedAt",
+  "accounts",
+  "address",
+  "emailAddress",
+  "phoneNumber",
+  "title",
+  "targetLists",
+  "campaign",
+  "cTags"
+]

espocrm-custom/custom/Espo/Custom/Resources/layouts/Lead/bottomPanelsDetail.json

@@ -0,0 +1,8 @@
+{
+  "targetLists": {
+    "index": 5
+  },
+  "cTags": {
+    "index": 6
+  }
+}

espocrm-custom/custom/Espo/Custom/Resources/layouts/Lead/filters.json

@@ -0,0 +1,20 @@
+[
+  "assignedUser",
+  "teams",
+  "createdAt",
+  "createdBy",
+  "modifiedAt",
+  "streamUpdatedAt",
+  "address",
+  "accountName",
+  "campaign",
+  "emailAddress",
+  "phoneNumber",
+  "status",
+  "source",
+  "opportunityAmountConverted",
+  "industry",
+  "targetLists",
+  "createdAccount",
+  "cTags"
+]

espocrm-custom/custom/Espo/Custom/Resources/layouts/Opportunity/filters.json

@@ -0,0 +1,20 @@
+[
+  "assignedUser",
+  "teams",
+  "createdAt",
+  "createdBy",
+  "modifiedAt",
+  "streamUpdatedAt",
+  "account",
+  "cAccount1",
+  "amountConverted",
+  "amountWeightedConverted",
+  "campaign",
+  "closeDate",
+  "contacts",
+  "leadSource",
+  "probability",
+  "stage",
+  "description",
+  "cTags"
+]

espocrm-custom/custom/Espo/Custom/Resources/metadata/clientDefs/CTag.json

@@ -15,6 +15,10 @@
         "firmen": {
             "layout": null,
             "selectPrimaryFilterName": null
+        },
+        "interessenten": {
+            "layout": null,
+            "selectPrimaryFilterName": null
         }
     }
 }

espocrm-custom/custom/Espo/Custom/Resources/metadata/clientDefs/Lead.json

@@ -0,0 +1,8 @@
+{
+  "relationshipPanels": {
+    "cTags": {
+      "create": false,
+      "rowActionsView": "custom:views/record/row-actions/tags-unlink-only"
+    }
+  }
+}

espocrm-custom/custom/Espo/Custom/Resources/metadata/entityDefs/Account.json

@@ -15,5 +15,12 @@
       "audited": false,
       "isCustom": true
     }
+  },
+  "fields": {
+    "cTags": {
+      "type": "linkMultiple",
+      "view": "views/fields/link-multiple",
+      "isCustom": true
+    }
   }
 }

espocrm-custom/custom/Espo/Custom/Resources/metadata/entityDefs/CTag.json

@@ -78,6 +78,14 @@
       "entity": "Account",
       "audited": false,
       "isCustom": true
+    },
+    "interessenten": {
+      "type": "hasMany",
+      "relationName": "cLeadTag",
+      "foreign": "cTags",
+      "entity": "Lead",
+      "audited": false,
+      "isCustom": true
     }
   },
   "collection": {

espocrm-custom/custom/Espo/Custom/Resources/metadata/entityDefs/Contact.json

@@ -8,5 +8,12 @@
       "audited": false,
       "isCustom": true
     }
+  },
+  "fields": {
+    "cTags": {
+      "type": "linkMultiple",
+      "view": "views/fields/link-multiple",
+      "isCustom": true
+    }
   }
 }

espocrm-custom/custom/Espo/Custom/Resources/metadata/entityDefs/Lead.json

@@ -0,0 +1,19 @@
+{
+    "fields": {
+        "cTags": {
+            "type": "linkMultiple",
+            "view": "views/fields/link-multiple",
+            "isCustom": true
+        }
+    },
+    "links": {
+        "cTags": {
+            "type": "hasMany",
+            "relationName": "cLeadTag",
+            "foreign": "interessenten",
+            "entity": "CTag",
+            "audited": false,
+            "isCustom": true
+        }
+    }
+}

espocrm-custom/custom/Espo/Custom/Resources/metadata/entityDefs/Opportunity.json

@@ -145,6 +145,11 @@
     },
     "closeDate": {
       "required": false
+    },
+    "cTags": {
+      "type": "linkMultiple",
+      "view": "views/fields/link-multiple",
+      "isCustom": true
     }
   },
   "links": {