Revert "Revert "lib/anubis: support setting extended cookie flags""

[Xe]

Reverts #134

[Copilot]

Pull Request Overview

This PR reverts a previous revert to reintroduce extended cookie flag support in Anubis. It re-applies cookie options (name, domain, partitioned flag) in the server and related HTTP functions, updates command-line flags, and adjusts tests to validate cookie settings.

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
lib/anubis_test.go	Updates test helpers and adds a new test for cookie settings.
cmd/anubis/main.go	Introduces new flags for cookie options.
docs/docs/CHANGELOG.md	Updates changelog with the extra cookie options information.
lib/anubis.go	Propagates new cookie options in server initialization and cookie handling.
lib/http.go	Converts ClearCookie to a method on Server to incorporate cookie options.

Files not reviewed (1)

• docs/docs/admin/installation.mdx: Language not supported

Comments suppressed due to low confidence (1)

lib/anubis_test.go:106

• Consider adding an assertion to verify that the cookie's 'Partitioned' flag is set correctly, similar to the check for the cookie domain.

if found && cookie.Domain != "local.cetacean.club" {