refactor: remove serde from domain entities for Clean Architecture compliance

- Remove Serialize/Deserialize from File, Folder, Session, User, Contact entities
- Create contact_persistence_dto.rs for JSONB persistence in infrastructure layer
- Update contact_pg_repository to use persistence DTOs
- Fix dependency on zip crate (downgrade from 7.2.0 to 2.1.0)
- Fix unused variable warnings in main.rs
- Move PathService import from domain to infrastructure
- Add missing fields to CoreServices and RepositoryServices
- Create proper service initialization in main.rs

Clean Architecture improvements:
- Domain layer no longer depends on serde framework
- Persistence concerns isolated to infrastructure layer
- TokenClaims in auth_service.rs is only exception (required for JWT)

SECURITY.md

@@ -1,44 +0,0 @@
-# Security Policy
-
-## Supported Versions
-
-The following versions of OxiCloud are currently supported with security updates:
-
-| Version | Supported          |
-| ------- | ------------------ |
-| Latest  | :white_check_mark: |
-
-## Reporting a Vulnerability
-
-The OxiCloud team takes security issues seriously. We appreciate your efforts to responsibly disclose your findings and will make every effort to acknowledge your contributions.
-
-To report a security vulnerability, please follow these steps:
-
-1. **DO NOT** disclose the vulnerability publicly (e.g., in GitHub issues)
-2. Email details of the vulnerability to the project maintainers
-3. Include as much information as possible, such as:
-   - A clear description of the vulnerability
-   - Steps to reproduce the issue
-   - Potential impact
-   - Suggested fixes if available
-
-## What to Expect
-
-After submitting a vulnerability report, you can expect the following:
-
-1. **Acknowledgment**: The team will acknowledge receipt of your report within 3 business days
-2. **Assessment**: We'll evaluate the vulnerability and determine its impact
-3. **Plan**: We'll develop a plan to address the vulnerability
-4. **Fix & Release**: Once fixed, we'll release an update
-5. **Recognition**: With your permission, we'll acknowledge your contribution in the release notes
-
-## Security Best Practices for OxiCloud Users
-
-- Keep your OxiCloud installation updated to the latest version
-- Use strong, unique passwords for all user accounts
-- Configure proper file permissions
-- Regularly back up your data
-- Consider running OxiCloud behind a reverse proxy with HTTPS
-- Implement IP restrictions where appropriate
-
-Thank you for helping keep OxiCloud and its users secure!