feat(region): add GOV/FedRAMP region support

[pranav-new-relic]

Summary

• Accepts both GOV and FEDRAMP as valid values for NEW_RELIC_REGION — via environment variable, newrelic profile add --region, and newrelic config set
• Bumps newrelic-client-go to v2.91.0 which introduces the GOV region with FedRAMP-compliant endpoints
• Updates all user-facing strings (error messages, help flags) to list both GOV and FEDRAMP
• Adds an explicit GOV/FEDRAMP branch in platform_link_generator; falls back to one.newrelic.com since no public GOV platform hostname exists

FEDRAMP is a user-facing alias for GOV. Both flow through nrRegion.Parse() which normalises either to region.GOV, ensuring consistent FedRAMP-compliant endpoint selection regardless of spelling.

Changes

File	What changed
go.mod	newrelic-client-go v2.86.1 → v2.91.0 (drops local replace directive)
internal/config/config.go	Added "FEDRAMP" to StringInStrings allowed list (case-insensitive)
internal/install/command.go	Error message lists "GOV" and "FEDRAMP"
internal/profile/command.go	Valid values slice and --region flag description include FEDRAMP
internal/install/execution/platform_link_generator.go	Explicit GOV/FEDRAMP case with US fallback and comment

Endpoint summary (from v2.91.0 Go client)

Field	GOV URL	Status
NerdGraph	gov-api.newrelic.com/graphql	✅ confirmed 200
Infrastructure	gov-infra-api.newrelic.com/v2	✅ infra agent reports successfully
Insights/Event API	gov-insights-collector.newrelic.com/v1	✅ confirmed 200; US endpoint 403s
Logs	gov-log-api.newrelic.com/log/v1	✅ per FedRAMP docs
Metrics	gov-metric-api.newrelic.com/metric/v1	✅ per FedRAMP docs
REST	gov-api.newrelic.com/v2	Same host as NerdGraph
Synthetics / InsightsKeys / Blob	US fallback	No GOV variants exist (DNS 000)

Test plan

• newrelic profile add --region GOV — accepted, stored as gov
• newrelic profile add --region FEDRAMP — accepted (new), stored as fedramp
• NEW_RELIC_REGION=GOV newrelic install -n ebpf-agent-installer — all requests route to gov-api.newrelic.com and gov-insights-collector.newrelic.com; install completes successfully on Ubuntu 22.04 EC2
• NEW_RELIC_REGION=FEDRAMP via env var — accepted, Parse("fedramp") returns region.GOV
• US insights-collector 403s with GOV license key; GOV insights-collector 200s — confirms correct cell routing

Known gaps (separate work items)

1. eBPF agent (Kapil's team): v1.4.5 maps region=GOV to otlp.nr-data.net (US OTLP) instead of gov-otlp.nr-data.net → 403 on all OTLP exports. Fix is in env.cc of the eBPF binary.
2. Infra recipe (open-install-library): infrastructure-agent-installer recipe does not write fedramp: true to /etc/newrelic-infra.yml when the region is GOV. Without it the infra agent 401s against the US ingest endpoint.

🤖 Generated with Claude Code

[pranav-new-relic]

Note on failing Windows E2E checks

The three failing checks (EU-windows2019.json, JP-windows2019.json, infra-win2016.json) are a pre-existing infrastructure flakiness issue unrelated to the changes in this PR.

Evidence: PR #1854 (an unrelated profile fix, open for weeks) has the exact same three Windows failures — #1854

Root cause: The Windows E2E tests install the infra agent via MSI on t3.micro EC2 instances in EU/JP AWS regions. The MSI installation occasionally exceeds the 234-second Ansible timeout under degraded EC2 performance. The failure message is always Failed to validate that Infrastructure Agent\s+\(installed\) is in output — meaning the install started but didn't complete in time.

Our changes only touch:

• internal/config/config.go — adds FEDRAMP to allowed region values
• internal/install/command.go — updates an error message string
• internal/install/execution/platform_link_generator.go — adds a URL branch for GOV/FEDRAMP
• internal/profile/command.go — adds FEDRAMP to valid values list
• go.mod / go.sum — bumps newrelic-client-go v2.86.1 → v2.91.0

None of these touch the Windows install path. All other checks (Linux infra, compile, lint, unit tests, integration tests) pass cleanly.

Requesting reviewer override on the Windows checks. Happy to provide any additional evidence.

[pranav-new-relic]

good for a temporary addition; let's harden this in upcoming PRs