fix(v2): use the real Bot Coordenador Slack credential and CHAMADOS SUPORTE channel

The user provided the real, dedicated Slack destination for this
automation (a separate Bot app credential + its channel), correcting my
earlier inference (the shared "Slack account" credential + $vars.
SLACK_CHANNEL_TECNICO, borrowed from an unrelated archived workflow,
which Slack's own API rejected as invalid_arguments in the prior test).

Created a new slackApi credential ("Slack - Bot Coordenador (Chamados
Suporte)", id lNqwBBrtLfkRqw2X) via n8n_manage_credentials -- the token
was created directly through the n8n credentials API and never written
to any file, workflow parameter, or commit; only the credential's id/name
reference (not a secret) is stored in the workflow, same as every other
credential in this project. Slack - Enviar Mensagem now targets channel
"CHAMADOS SUPORTE" by name instead of the unresolved variable.

158/158 tests passing.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

n8n/deployed/coordenador-glpi-v2.n8n.json

@@ -784,16 +784,16 @@
         "select": "channel",
         "channelId": {
           "__rl": true,
-          "mode": "id",
-          "value": "={{ $vars.SLACK_CHANNEL_TECNICO }}"
+          "mode": "name",
+          "value": "CHAMADOS SUPORTE"
         },
         "text": "={{ $json.mensagem }}",
         "otherOptions": {}
       },
       "credentials": {
         "slackApi": {
-          "id": "ER8aVNhPGAN0H5Am",
-          "name": "Slack account"
+          "id": "lNqwBBrtLfkRqw2X",
+          "name": "Slack - Bot Coordenador (Chamados Suporte)"
         }
       }
     },

n8n/workflow.template.json

@@ -784,16 +784,16 @@
         "select": "channel",
         "channelId": {
           "__rl": true,
-          "mode": "id",
-          "value": "={{ $vars.SLACK_CHANNEL_TECNICO }}"
+          "mode": "name",
+          "value": "CHAMADOS SUPORTE"
         },
         "text": "={{ $json.mensagem }}",
         "otherOptions": {}
       },
       "credentials": {
         "slackApi": {
-          "id": "ER8aVNhPGAN0H5Am",
-          "name": "Slack account"
+          "id": "lNqwBBrtLfkRqw2X",
+          "name": "Slack - Bot Coordenador (Chamados Suporte)"
         }
       }
     },