fix(matchexpr): expose 'isAgent' field for evaluation (backport #598)

[mergify]

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---

Fixes: cryostatio/cryostat-web#1320

Before:

After:

---

This is an automatic backport of pull request #598 done by [Mergify](https://mergify.com).

[andrewazores]

/build_test

[github-actions]

Workflow started at 8/9/2024, 4:57:34 PM. View Actions Run.

[github-actions]

No GraphQL schema changes detected.

[github-actions]

OpenAPI schema change detected:

diff --git a/schema/openapi.yaml b/schema/openapi.yaml
index 96e94aa..776f3ae 100644
--- a/schema/openapi.yaml
+++ b/schema/openapi.yaml
@@ -355,21 +355,21 @@ components:
 info:
   contact:
     email: cryostat-development@googlegroups.com
     name: Cryostat Community
     url: https://cryostat.io
   description: Cloud-Native JDK Flight Recorder
   license:
     name: Apache 2.0
     url: https://github.com/cryostatio/cryostat3/blob/main/LICENSE
   title: Cryostat API
-  version: 3.0.0-snapshot
+  version: 3.0.1-snapshot
 openapi: 3.0.3
 paths:
   /api/beta/credentials/{connectUrl}:
     post:
       parameters:
         - in: path
           name: connectUrl
           required: true
           schema:
             type: string

[github-actions]

Schema changes committed by the CI.

[github-actions]

CI build and push: All tests pass ✅
https://github.com/cryostatio/cryostat/actions/runs/10325612728