Document every exported symbol and how callers use the library.

Co-authored-by: Cursor <cursoragent@cursor.com>

preferences.go

@@ -38,6 +38,8 @@ func (p AppAPIPreferences) ocsClient() OCSClient {
 }
 
 // Get loads the configured preference key for the requesting user.
+// A missing key returns an empty string and a nil error.
+// It returns an error when the OCS call fails or the body cannot be decoded.
 func (p AppAPIPreferences) Get() (string, error) {
 	ocs := p.ocsClient()
 	body, _ := json.Marshal(map[string]any{"configKeys": []string{p.Key}})
@@ -49,6 +51,8 @@ func (p AppAPIPreferences) Get() (string, error) {
 }
 
 // Set stores value for the configured preference key.
+// The value is stored as non-sensitive.
+// It returns an error when the OCS call fails.
 func (p AppAPIPreferences) Set(value string) error {
 	ocs := p.ocsClient()
 	body, _ := json.Marshal(map[string]any{