fix: address review - prefix unused params with underscore and update ROADMAP

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

ROADMAP.md

@@ -329,6 +329,7 @@ business/custom objects, aligning with industry best practices (e.g., ServiceNow
 **Migration (v3.x → v4.0):**
 - v3.x: The `SystemObjectName` constants now emit `sys_`-prefixed names. Implementations using `StorageNameMapping.resolveTableName()` can set `tableName` to preserve legacy physical table names during the transition.
 - v3.x: The `@objectstack/plugin-auth` ObjectQL adapter now includes `AUTH_MODEL_TO_PROTOCOL` mapping to translate better-auth's hardcoded model names (`user`, `session`, `account`, `verification`) to protocol names (`sys_user`, `sys_session`, `sys_account`, `sys_verification`). Custom adapters must adopt the same mapping.
+- v3.x: **Enhancement** — `AuthManager` now uses better-auth's official `modelName` / `fields` schema customisation API (`AUTH_USER_CONFIG`, `AUTH_SESSION_CONFIG`, `AUTH_ACCOUNT_CONFIG`, `AUTH_VERIFICATION_CONFIG`) to declare camelCase → snake_case field mappings. The ObjectQL adapter uses `createAdapterFactory` from `better-auth/adapters` to apply these transformations automatically, eliminating the need for manual field-name conversion. The legacy `createObjectQLAdapter()` is retained for backward compatibility.
 - v3.x: **Bug fix** — `AuthManager.createDatabaseConfig()` now wraps the ObjectQL adapter as a `DBAdapterInstance` factory function (`(options) => DBAdapter`). Previously the raw adapter object was passed, which fell through to the Kysely adapter path and failed silently. `AuthManager.handleRequest()` and `AuthPlugin.registerAuthRoutes()` now inspect `response.status >= 500` and log the error body, since better-auth catches internal errors and returns 500 Responses without throwing.
 - v3.x: **Bug fix** — `AuthPlugin` now defers HTTP route registration to a `kernel:ready` hook instead of doing it synchronously in `start()`. This makes the plugin resilient to plugin loading order — the `http-server` service is guaranteed to be available after all plugins complete their init/start phases. The CLI `serve` command also registers `HonoServerPlugin` before config plugins (with duplicate detection) for the same reason.
 - v4.0: Legacy un-prefixed aliases will be fully removed.

packages/plugins/plugin-auth/src/objectql-adapter.ts

@@ -95,25 +95,24 @@ export function createObjectQLAdapterFactory(dataEngine: IDataEngine) {
     },
     adapter: () => ({
       create: async <T extends Record<string, any>>(
-        { model, data }: { model: string; data: T; select?: string[] },
+        { model, data, select: _select }: { model: string; data: T; select?: string[] },
       ): Promise<T> => {
         const result = await dataEngine.insert(model, data);
         return result as T;
       },
 
       findOne: async <T>(
-        { model, where, select }: { model: string; where: CleanedWhere[]; select?: string[]; join?: any },
+        { model, where, select, join: _join }: { model: string; where: CleanedWhere[]; select?: string[]; join?: any },
       ): Promise<T | null> => {
         const filter = convertWhere(where);
 
-        // Note: join is not currently supported by ObjectQL's findOne operation
         const result = await dataEngine.findOne(model, { filter, select });
 
         return result ? (result as T) : null;
       },
 
       findMany: async <T>(
-        { model, where, limit, offset, sortBy }: {
+        { model, where, limit, offset, sortBy, join: _join }: {
           model: string; where?: CleanedWhere[]; limit: number;
           offset?: number; sortBy?: { field: string; direction: 'asc' | 'desc' }; join?: any;
         },