Fix stale references to schema.graphql and v1_resolver.go

Update GNUmakefile targets to use wildcard graphql/*.graphql
prerequisites instead of the deleted schema.graphql files, and
remove v1_resolver.go from build prerequisites.

Also update .gitattributes, package.json graphql.schema path,
and AGENTS.md.

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

package.json

@@ -23,7 +23,7 @@
     "turbo": "^2.5.3"
   },
   "graphql": {
-    "schema": "./pkg/server/api/console/v1/schema.graphql"
+    "schema": "./pkg/server/api/console/v1/graphql/"
   },
   "overrides": {
     "brace-expansion": "^5.0.5",