feat(plugins): show plugin logs on detail page via Docs/Logs tablist

Add a Logs tab beside Documentation on the plugin detail page, showing
the output a plugin prints through the standard Python logger (per the
wiki style guide). Logs are captured from the plugin's stderr by the
plugin runtime and fetched on demand.

- Bump langbot-plugin pin to 0.4.4 (adds GET_PLUGIN_LOGS action)
- plugin_connector/handler: get_plugin_logs RPC client
- HTTP route GET /api/v1/plugins/<author>/<name>/logs (limit + level)
- Frontend: wrap detail right panel in Docs/Logs Tabs; PluginLogs
  component with level filter, manual + 3s auto refresh, bottom-follow
- i18n: 7 new keys across all 8 locales

web/src/app/infra/http/BackendClient.ts

@@ -55,6 +55,7 @@ import {
   ApiRespSkill,
 } from '@/app/infra/entities/api';
 import { Plugin } from '@/app/infra/entities/plugin';
+import type { PluginLogEntry } from '@/app/infra/entities/plugin';
 import type { I18nObject } from '@/app/infra/entities/common';
 import { GetBotLogsRequest } from '@/app/infra/http/requestParam/bots/GetBotLogsRequest';
 import { GetBotLogsResponse } from '@/app/infra/http/requestParam/bots/GetBotLogsResponse';
@@ -604,6 +605,22 @@ export class BackendClient extends BaseHttpClient {
     );
   }
 
+  public getPluginLogs(
+    author: string,
+    name: string,
+    limit: number = 200,
+    level?: string,
+  ): Promise<{ logs: PluginLogEntry[] }> {
+    const params = new URLSearchParams();
+    params.set('limit', String(limit));
+    if (level) {
+      params.set('level', level);
+    }
+    return this.get(
+      `/api/v1/plugins/${author}/${name}/logs?${params.toString()}`,
+    );
+  }
+
   public getPluginAssetURL(
     author: string,
     name: string,