chore: upgrade backend to Laravel 13

[Liinkiing]

🎟️ Related issue

None.

❓ Context

This PR upgrades the Laravel backend template to Laravel 13 and aligns the surrounding backend defaults, package versions, and local Sail setup with the new framework baseline.

👨‍💻 Solution

• Upgrade backend Composer dependencies to Laravel 13-compatible versions, including Lighthouse, Sanctum, Socialite, Sail, Telescope, Pest, and tooling packages.
• Refresh Laravel 13 config defaults for cache, session, database, queue, logging, mail, filesystems, Sanctum, Lighthouse, and Telescope.
• Update backend migrations for Laravel 13 defaults and ULID users, including database sessions and personal access token compatibility.
• Add regression coverage for GraphQL query cache behavior and ULID users with database sessions.
• Adjust mobile auth routing/client logout flow for the updated backend API shape.

🧪 Testing plan

• ./vendor/bin/sail pest
• ./vendor/bin/sail bin phpstan
• ./vendor/bin/sail composer validate --strict
• ./vendor/bin/sail composer audit
• ./vendor/bin/sail artisan migrate --pretend
• docker compose config --services
• git diff --check