fix: Correct EPG scan time configuration and improve old file removal…

… logic

chore: Update Go base image to version 1.24.0 in Dockerfile

chore: Update Go version to 1.24.0 in build workflow

fix: Adjust timestamp handling for daylight saving time in EPG requests

Change log level for access denial and retrieval success messages

Implement memory and null authentication providers

- Added MemoryAuthProvider for in-memory user management including user authentication, addition, removal, and role management.
- Introduced NullAuthProvider as a placeholder that allows all authentication requests to succeed without actual user management.
- Defined AuthProvider interface to standardize authentication provider implementations.
- Created User and UserView structs to represent user data and views.
- Implemented JWT token creation and verification functions for user authentication.
- Integrated logging functionality throughout the authentication and stream handling processes.
- Updated stream server to utilize the new authentication providers and logging.
- Refactored existing code to replace references to the old authentication package with the new m3uproxy authentication package.

Refactor CLI commands and enhance user management features with API i…

…ntegration

Fix proxy URL handling in NewUpstreamConnection to exclude path

Enhance upstream connection handling with proxy support and improve e…

…rror logging

Add diagnostic capabilities to sources and API handler

- Introduced SourcesDiag struct for diagnostic information.
- Implemented Diagnostic method in Sources to gather diagnostics.
- Added Diagnostic method in StreamSource interface.
- Enhanced BaseStreamSource with diagnostic logic.
- Updated APIHandler to handle diagnostic requests.
- Added GetChannel method in ChannelsHandler for channel retrieval.