export declare const builtInAvatars: Record<string, string>;
export declare const builtInAvatarIds: string[];
export declare const WHITE_BG_AVATARS: Set<string>;
export declare const THEME_BG_AVATARS: Set<string>;
/** Returns the CSS background value for an avatar container based on the avatar type. */
export declare function avatarContainerBg(key: string | undefined): string;
/** Returns the effective avatar key after resolving fallbacks.
 *  Unknown built-in IDs (e.g. a removed avatar) normalise to 'bubble'.
 *  External URLs are returned as-is. */
export declare function effectiveAvatarKey(value: string | undefined): string | undefined;
/** Resolve a user-supplied value to a URL suitable for <img src>.
 *  Unknown built-in IDs fall back to the 'bubble' icon. */
export declare function resolveAvatarUrl(value: string | undefined): string | undefined;