chore: добавить frontend правила и шаблоны SLM

- добавлены frontend инструкции AGENTS и локальный style guide
- актуализированы SLM templates под Vite React и слой infra
- добавлены шаблоны component, infra и factory-based business
- нормализованы примеры документации под alias infra

.templates/infra/{{name.kebabCase}}/errors/{{name.kebabCase}}.error.ts

@@ -0,0 +1,12 @@
+/**
+ * Ошибка API {{name.pascalCase}}.
+ */
+export class {{name.pascalCase}}Error extends Error {
+  constructor(
+    public readonly status: number,
+    message: string,
+  ) {
+    super(message)
+    this.name = '{{name.pascalCase}}Error'
+  }
+}

.templates/infra/{{name.kebabCase}}/index.ts

@@ -0,0 +1,3 @@
+export { {{name.pascalCase}}Client, create{{name.pascalCase}}Client } from './{{name.kebabCase}}.client'
+export { {{name.pascalCase}}Error } from './errors/{{name.kebabCase}}.error'
+export type { QueryParams } from './types/{{name.kebabCase}}-client.type'

.templates/infra/{{name.kebabCase}}/types/{{name.kebabCase}}-client.type.ts

@@ -0,0 +1,4 @@
+/**
+ * Query-параметры API {{name.pascalCase}}.
+ */
+export type QueryParams = Record<string, boolean | number | string | null | undefined>

.templates/infra/{{name.kebabCase}}/{{name.kebabCase}}.client.ts

@@ -0,0 +1,44 @@
+import { {{name.pascalCase}}Error } from './errors/{{name.kebabCase}}.error'
+import type { QueryParams } from './types/{{name.kebabCase}}-client.type'
+
+/**
+ * REST-клиент {{name.pascalCase}}.
+ */
+export class {{name.pascalCase}}Client {
+  constructor(
+    private readonly baseUrl: string,
+    private readonly defaultHeaders: Record<string, string> = {},
+  ) {}
+
+  /**
+   * Выполняет GET-запрос к API {{name.pascalCase}}.
+   */
+  async get<T>(path: string, params: QueryParams = {}): Promise<T> {
+    const base = `${this.baseUrl.replace(/\/+$/, '')}/`
+    const url = new URL(path.replace(/^\/+/, ''), base)
+
+    Object.entries(params).forEach(([key, value]) => {
+      if (value !== null && value !== undefined) {
+        url.searchParams.set(key, String(value))
+      }
+    })
+
+    const response = await fetch(url, {
+      headers: {
+        Accept: 'application/json',
+        ...this.defaultHeaders,
+      },
+    })
+
+    if (!response.ok) {
+      throw new {{name.pascalCase}}Error(response.status, response.statusText)
+    }
+
+    return response.json() as Promise<T>
+  }
+}
+
+/**
+ * Создаёт REST-клиент {{name.pascalCase}} с заданным base URL.
+ */
+export const create{{name.pascalCase}}Client = (baseUrl: string) => new {{name.pascalCase}}Client(baseUrl)