fix: snapshot reporting use HTTP_PROXY and HTTPS_PROXY env vars

[shazlehu]

Proposed Change

The AgentClient wrapper around http.Client (used to add headers to snapshot reports) didn't include a proxy setting in its Transport, so snapshots failed in environments configured with a proxy and without DNS access, specifically for Windows.

Testing

We have a proxy configured on the localnet at bp-qa-ub-proxy.bluemedora.localnet:9094

See https://observiq.com/docs/advanced-setup/configuration/proxy for setting up an agent with a proxy. The current agent will create an error when the snapshot console is opened in BP, with this PR snapshot should appear normally.

For Windows:

Using regedit, add to the Environment key for observiq-otel-collector

HTTP_PROXY=http://bp-qa-ub-proxy.bluemedora.localnet:9094
HTTPS_PROXYhttp://bp-qa-ub-proxy.bluemedora.localnet:9094

Restart the collector using Services.

For macOS agent:

Add HTTP_PROXY and HTTPS_PROXY to the EnvironmentVariables dict in the launchd service file /Library/LaunchDaemons/com.observiq.collector.plist (other values are shown for context):

<key>EnvironmentVariables</key>
<dict>
    <key>HTTP_PROXY</key>
    <string>http://bp-qa-ub-proxy.bluemedora.localnet:9094</string>    
    <key>HTTPS_PROXY</key>
    <string>http://bp-qa-ub-proxy.bluemedora.localnet:9094</string>    
    <key>OIQ_OTEL_COLLECTOR_HOME</key>
    <string>/opt/observiq-otel-collector/</string>
    <key>OIQ_OTEL_COLLECTOR_STORAGE</key>
    <string>/opt/observiq-otel-collector/storage</string>
</dict>

Then restart the agent:

sudo launchctl unload /Library/LaunchDaemons/com.observiq.collector.plist
sudo launchctl load /Library/LaunchDaemons/com.observiq.collector.plist

Checklist

• Changes are tested
• CI has passed

[dpaasman00]

LGTM - verified good behavior on linux