Add Newsletter #75 and update agent guide

Added the Newsletter #75 post with technical interview, microservices, Linux kernel, and load balancer insights. Updated AGENTS.md to clarify language usage and remove command examples. Extended allowed Bash commands in settings.local.json to include powershell.

AGENTS.md

@@ -1,20 +1,14 @@
 # AGENTS.md
 
-Guide for AI code assistants working with this Hugo blog (miti99.com).
+Guide for AI code assistants working with this Hugo blog.
 
 ## Project Info
 
 - **Type**: Hugo static site with Vietnamese tech content
 - **Theme**: hugo-theme-stack
-- **Language**: Vietnamese (with common English tech terms)
+- **Language**: Vietnamese (with common English tech words)
 - **Timezone**: Asia/Ho_Chi_Minh (UTC+7)
 
-## Commands
-```bash
-hugo server --gc     # Local dev
-hugo --gc --minify   # Production build
-```
-
 ## Directory Structure
 ```
 content/post/
@@ -138,7 +132,7 @@ Group assets by type with subheadings:
 
 ### Vietnamese Writing
 - **Primary language**: Vietnamese
-- **English allowed**: Tech terms (API, GitHub, AI, backend, frontend, etc.)
+- **English allowed**: Tech terms (API, GitHub, AI, backend, frontend, etc.), but limited, use Vietnamese if possible
 - **Audience**: Junior developers
 - **Tone**: Professional, clear, accessible
 - **Length**: Max 300 words per summary