fix: replace deprecated Slack actions with mrkdwn link field

The actions array in Slack attachments requires Interactive Components
to be configured on the Slack app, which causes notifications to fail.
Replaces with a Details field using mrkdwn hyperlink syntax and adds
mrkdwn_in to ensure the link renders as clickable.

Closes #4053

packages/server/src/utils/notifications/build-error.ts

@@ -240,14 +240,13 @@ export const sendBuildErrorNotifications = async ({
 									value: `\`\`\`${errorMessage}\`\`\``,
 									short: false,
 								},
-							],
-							actions: [
 								{
-									type: "button",
-									text: "View Build Details",
-									url: buildLink,
+									title: "Details",
+									value: `<${buildLink}|View Build Details>`,
+									short: false,
 								},
 							],
+							mrkdwn_in: ["fields"],
 						},
 					],
 				});

packages/server/src/utils/notifications/build-success.ts

@@ -256,14 +256,13 @@ export const sendBuildSuccessNotifications = async ({
 									value: date.toLocaleString(),
 									short: true,
 								},
-							],
-							actions: [
 								{
-									type: "button",
-									text: "View Build Details",
-									url: buildLink,
+									title: "Details",
+									value: `<${buildLink}|View Build Details>`,
+									short: false,
 								},
 							],
+							mrkdwn_in: ["fields"],
 						},
 					],
 				});