feat(agent): implement HTTP-based recordings queries to -agents

[andrewazores]

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---

See #1415 #1419
Related to #1416
Related to #1309
Related to #520

Description of the change:

Like #1415 and #1419. This one queries information about active recordings.

Motivation for the change:

Same as before

How to manually test:

Needs cryostatio/cryostat-agent#82
Apply the following patch:

diff --git a/smoketest.sh b/smoketest.sh
index 4aebf722..15dbd3f4 100755
--- a/smoketest.sh
+++ b/smoketest.sh
@@ -158,7 +158,7 @@ runDemoApps() {
         --env CRYOSTAT_AGENT_BASEURI="${protocol}://localhost:${webPort}/" \
         --env CRYOSTAT_AGENT_TRUST_ALL="true" \
         --env CRYOSTAT_AGENT_AUTHORIZATION="Basic $(echo user:pass | base64)" \
-        --env CRYOSTAT_AGENT_REGISTRATION_PREFER_JMX="true" \
+        --env CRYOSTAT_AGENT_REGISTRATION_PREFER_JMX="false" \
         --env CRYOSTAT_AGENT_HARVESTER_PERIOD_MS=60000 \
         --env CRYOSTAT_AGENT_HARVESTER_MAX_FILES=10 \
         --rm -d quay.io/andrewazores/quarkus-test:latest

Testing procedure is the same as before, but this time go to the Recordings view. Select the quarkus-test-agent with port 9977 sample application. The active recordings table should populate.

[github-actions]

Test image available:

$ CRYOSTAT_IMAGE=ghcr.io/cryostatio/cryostat:pr-1423-3c747e213da163ddc1ffb757f826e3c3f2c38c4f sh smoketest.sh

[maxcao13]

Looks good then, just needs a rebase.

[github-actions]

Test image available:

$ CRYOSTAT_IMAGE=ghcr.io/cryostatio/cryostat:pr-1423-48f2b2bac0d5e1aed413c790186be30e618c4f6a sh smoketest.sh