feat: Implement directory validation and shell command quoting

- Added is_valid_directory function to validate directory paths, ensuring they do not contain control characters and are within a specified length.
- Introduced quote_shell_arg to safely quote shell arguments, preventing command injection.
- Created build_cd_command to generate a command for changing directories in a shell.
- Enhanced the LoginHandler to utilize a login rate limiter, preventing brute-force attacks by tracking failed login attempts.
- Implemented an EncodingCache to optimize encoding detection for SSH connections.
- Updated the UI to include an input field for specifying an initial directory upon login, with appropriate validation and hints.
- Added a quickbar in the terminal interface for easy access to copy and paste functionality.
- Introduced a toast notification system to provide feedback on copy actions.
- Refactored connection storage to encrypt passwords at rest, improving security.
- Updated various templates and styles to accommodate new features and improve user experience.

docker-compose.yml

@@ -7,6 +7,13 @@ services:
     restart: unless-stopped
     ports:
       - "8888:8888"
+    environment:
+      # extra wssh options, e.g. "--maxconn=50 --tdstream=172.18.0.1"
+      WEBSSH_OPTS: ${WEBSSH_OPTS:-}
+      # set this to keep saved passwords readable across container rebuilds
+      # when the data volume is recreated; otherwise a secret is generated
+      # in /data on first start
+      WEBSSH_COOKIE_SECRET: ${WEBSSH_COOKIE_SECRET:-}
     volumes:
       - webssh-data:/data