Migrate configuration from environment variables to YAML file

- Add YAML-based configuration loaded from config.yaml (CONFIG_LOCATION env var)
  - Add PyYAML dependency and install requirements in Dockerfile
  - Replace Config.from_env() with get_config() singleton pattern
  - Remove server_header from config (now randomized from wordlists only)
  - Update docker-compose.yaml to mount config.yaml read-only
  - Update Helm chart: restructure values.yaml, generate config.yaml in ConfigMap
  - Update Kubernetes manifests: ConfigMap now contains config.yaml, deployments mount it
  - Remove Helm secret.yaml (dashboard path now auto-generated in config.yaml)

src/generators.py

@@ -9,8 +9,6 @@ import string
 import json
 from templates import html_templates
 from wordlists import get_wordlists
-from config import Config
-from logger import get_app_logger
 
 def random_username() -> str:
     """Generate random username"""
@@ -38,15 +36,9 @@ def random_email(username: str = None) -> str:
     return f"{username}@{random.choice(wl.email_domains)}"
 
 def random_server_header() -> str:
-    """Generate random server header"""
-    
-    if Config.from_env().server_header:
-        server_header = Config.from_env().server_header
-    else:
-        wl = get_wordlists()
-        server_header = random.choice(wl.server_headers)
-    
-    return server_header
+    """Generate random server header from wordlists"""
+    wl = get_wordlists()
+    return random.choice(wl.server_headers)
 
 def random_api_key() -> str:
     """Generate random API key"""