Make tracker pattern displayName read-only

The displayName field was always predictable from pattern + matchType
and allowing edits added unnecessary complexity. Remove displayName
from UpdateTrackerPatternInput across all surfaces (GraphQL, MCP, CLI,
n8n) and make the frontend show it as non-editable text.

Signed-off-by: Émile Ré <emile@getprobo.com>

pkg/server/api/console/v1/graphql/cookie_banner.graphql

@@ -517,7 +517,6 @@ input CreateTrackerPatternInput {
 
 input UpdateTrackerPatternInput {
     trackerPatternId: ID!
-    displayName: String
     maxAgeSeconds: Int @goField(omittable: true)
     description: String
     excluded: Boolean