feat(provider): expose registry spec files

Add stable registry helpers for enumerating provider OpenAPI spec files, plus iterator coverage. This gives discovery consumers a direct way to aggregate provider docs without changing routing behaviour.

Co-Authored-By: Virgil <virgil@lethean.io>

pkg/provider/registry.go

@@ -152,3 +152,32 @@ func (r *Registry) Info() []ProviderInfo {
 	}
 	return infos
 }
+
+// SpecFiles returns all non-empty provider OpenAPI spec file paths.
+// The result is deduplicated and sorted for stable discovery output.
+func (r *Registry) SpecFiles() []string {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+
+	files := make(map[string]struct{}, len(r.providers))
+	for _, p := range r.providers {
+		if sf, ok := p.(interface{ SpecFile() string }); ok {
+			if path := sf.SpecFile(); path != "" {
+				files[path] = struct{}{}
+			}
+		}
+	}
+
+	out := make([]string, 0, len(files))
+	for path := range files {
+		out = append(out, path)
+	}
+
+	slices.Sort(out)
+	return out
+}
+
+// SpecFilesIter returns an iterator over all non-empty provider OpenAPI spec files.
+func (r *Registry) SpecFilesIter() iter.Seq[string] {
+	return slices.Values(r.SpecFiles())
+}

pkg/provider/registry_test.go

@@ -38,6 +38,13 @@ func (r *renderableProvider) Element() provider.ElementSpec {
 	return provider.ElementSpec{Tag: "core-stub-panel", Source: "/assets/stub.js"}
 }
 
+type specFileProvider struct {
+	stubProvider
+	specFile string
+}
+
+func (s *specFileProvider) SpecFile() string { return s.specFile }
+
 type fullProvider struct {
 	streamableProvider
 }
@@ -177,3 +184,27 @@ func TestRegistry_Iter_Good(t *testing.T) {
 	}
 	assert.Equal(t, 2, count)
 }
+
+func TestRegistry_SpecFiles_Good(t *testing.T) {
+	reg := provider.NewRegistry()
+	reg.Add(&stubProvider{})
+	reg.Add(&specFileProvider{specFile: "/tmp/b.json"})
+	reg.Add(&specFileProvider{specFile: "/tmp/a.yaml"})
+	reg.Add(&specFileProvider{specFile: "/tmp/a.yaml"})
+	reg.Add(&specFileProvider{specFile: ""})
+
+	assert.Equal(t, []string{"/tmp/a.yaml", "/tmp/b.json"}, reg.SpecFiles())
+}
+
+func TestRegistry_SpecFilesIter_Good(t *testing.T) {
+	reg := provider.NewRegistry()
+	reg.Add(&specFileProvider{specFile: "/tmp/z.json"})
+	reg.Add(&specFileProvider{specFile: "/tmp/x.json"})
+
+	var files []string
+	for file := range reg.SpecFilesIter() {
+		files = append(files, file)
+	}
+
+	assert.Equal(t, []string{"/tmp/x.json", "/tmp/z.json"}, files)
+}