add description of plugin work as documentation in README.md

Author: kulikp1

README.md

@@ -1,4 +1,104 @@
-# AdminForth Auto Remove Plugin
+# Auto Remove Plugin
 
-Allows to remove old records.
+This plugin removes records from resources based on **count-based** or **time-based** rules.
 
+It is designed for cleaning up:
+
+* old records
+* logs
+* demo/test data
+* temporary entities
+
+---
+
+## Instalation
+
+To install the plugin:
+
+```bash
+npm install @adminforth/auto-remove
+```
+
+Import it into your resource:
+```bash
+import AutoRemovePlugin from '../../plugins/adminforth-auto-remove/index.js';
+```
+
+## Plugin Options
+
+```ts
+export interface PluginOptions {
+ createdAtField: string;
+
+  /**
+   * - count-based: Delete items > maxItems
+   * - time-based: Delete age > maxAge
+   */
+  mode: AutoRemoveMode;
+
+  /**
+   * for count-based mode (100', '1k', '10k', '1m')
+   */
+  keepAtLeast?: HumanNumber;
+
+  /**
+   * Minimum number of items to always keep in count-based mode.
+   * This acts as a safety threshold together with `keepAtLeast`.
+   * Example formats: '100', '1k', '10k', '1m'.
+   * 
+   * Validation ensures that minItemsKeep <= keepAtLeast. 
+  */
+  minItemsKeep?: HumanNumber;
+
+  /**
+   * Max age of item for time-based mode ('1d', '7d', '1mon', '1y')
+   */
+  deleteOlderThan?: HumanDuration;
+
+  /**
+   * Interval for running cleanup (e.g. '1h', '1d')
+   * Default '1d'
+   */
+  interval?: HumanDuration;
+}
+```
+---
+
+## Usage
+To use the plugin, add it to your resource file. Here's an example:
+
+for count-based mode
+```ts
+new AutoRemovePlugin({
+        createdAtField: 'created_at',   
+        mode: 'count-based',            
+        keepAtLeast: '200',                  
+        interval: '1s',                  
+        minItemsKeep: '180',       
+      }),
+```
+
+for time-based mode
+```ts
+new AutoRemovePlugin({
+        createdAtField: 'created_at',
+        mode: 'time-based',
+        deleteOlderThan: '3min',
+        interval: '5s',  
+      }),
+```
+
+---
+
+## Result
+After running **AutoRemovePlugin**, old or excess records are deleted automatically:
+
+- **Count-based mode:** keeps the newest `keepAtLeast` records, deletes older ones.  
+  Example: `keepAtLeast = 500` → table with 650 records deletes 150 oldest.
+
+- **Time-based mode:** deletes records older than `deleteOlderThan`.  
+  Example: `deleteOlderThan = '7d'` → removes records older than 7 days.
+
+- **Manual cleanup:** `POST /plugin/{pluginInstanceId}/cleanup`, returns `{ "ok": true }`.
+
+Logs show how many records were removed per run.