fix: add Go and Raw registries to metrics detection and health endpoint (#97)

detect_registry() in metrics.rs was missing branches for /go/ and /raw/
paths, causing all requests to those registries to be labeled "other" in
Prometheus metrics. dashboard_metrics.rs already lists all seven
registries, so this was an oversight.

Also adds go and raw fields to RegistriesHealth so the /health endpoint
reports all seven registries consistently.

Fixes the test_detect_registry_go_path test which previously asserted
the wrong behavior ("other" instead of "go"), and adds tests for raw
path detection and prefix collision safety.

// ticktockbent

Co-authored-by: DevITWay | Pavel Volkov <devitway@gmail.com>

CHANGELOG.md

@@ -1,4 +1,10 @@
 # Changelog
+## [Unreleased]
+
+### Fixed
+- Go and Raw registries missing from Prometheus metrics (`detect_registry` labeled both as "other")
+- Go and Raw registries missing from `/health` endpoint `registries` object
+
 ## [0.4.0] - 2026-04-05
 
 ### Added