fix: address santa-loop review findings (round 2)

Stage and commit remaining 4 title renames that were left as
unstaged working-tree changes:
- API.md: Languard Server Manager → Languard Servers Manager
- DATABASE.md: Languard Server Manager → Languard Servers Manager
- MODULES.md: Languard Server Manager → Languard Servers Manager
- THREADING.md: Languard Server Manager → Languard Servers Manager

API.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — API Contract
+# Languard Servers Manager — API Contract
 
 ## Base URL
 ```

ARCHITECTURE.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — System Architecture
+# Languard Servers Manager — System Architecture
 
 ## Overview
 
@@ -216,7 +216,7 @@ LANGUARD_LOG_RETENTION_DAYS=7
 ## Directory Layout
 
 ```
-languard-server-manager/
+languard-servers-manager/
 ├── backend/
 │   ├── main.py                    # FastAPI app factory
 │   ├── config.py                  # Settings from env

DATABASE.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — Database Design
+# Languard Servers Manager — Database Design
 
 ## Engine
 - **SQLite** via `SQLAlchemy Core` (sync for all access — routes and threads)

IMPLEMENTATION_PLAN.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — Implementation Plan
+# Languard Servers Manager — Implementation Plan
 
 ## Prerequisites
 
@@ -402,7 +402,7 @@ Verify React app can:
 ```bash
 # 1. Clone repo
 git clone <repo>
-cd languard-server-manager
+cd languard-servers-manager
 
 # 2. Backend
 cd backend

MODULES.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — Python Module Breakdown
+# Languard Servers Manager — Python Module Breakdown
 
 ## Project Structure
 

THREADING.md

@@ -1,4 +1,4 @@
-# Languard Server Manager — Threading & Concurrency Design
+# Languard Servers Manager — Threading & Concurrency Design
 
 ## Overview