feat: enhance application state management with cookie support

- Added cookie key to AppState for managing session cookies.
- Updated AppState initialization to derive cookie key from configuration.
- Removed session-based authentication option from cargo-generate prompts.
- Refactored JWT authentication logic to improve clarity and error handling.
- Updated password validation to align with NIST recommendations (minimum length increased).
- Removed unused session store implementation and related code.
- Improved error handling in user repository for unique constraint violations.
- Refactored OIDC service to include state management for authentication flow.
- Cleaned up dependencies in Cargo.toml and Cargo.toml.template for clarity and efficiency.

cargo-generate.toml

@@ -24,11 +24,6 @@ prompt = "Database type"
 choices = ["sqlite", "postgres"]
 default = "sqlite"
 
-[placeholders.auth_session]
-type = "bool"
-prompt = "Enable session-based authentication (cookies)?"
-default = true
-
 [placeholders.auth_jwt]
 type = "bool"
 prompt = "Enable JWT authentication (Bearer tokens)?"