feature: Add "Change Password" to Profile Settings

[builtbykabir]

Add "Change Password" to Profile Settings

Description

Currently, users (both Adventurers and Companies) have no way to change their password once they are logged in. The Profile Settings pages only allow users to update their name, bio, and website, completely omitting security management.

Proposed Fix

We need to add a dedicated section to the profile settings pages that allows users to securely update their credentials.
A simpler solution for now would be to use the forgot password mechanics.

Acceptance Criteria

• Both Adventurers and Companies can access the password change form in their respective profile settings.
• Users must provide their current password to authorize the change.
• Users who registered via OAuth see a clear message explaining why they cannot change a password.