feat: enable IPv6 on 1panel-network by default

[jakub961241]

Summary

Closes #12202 - Enable IPv6 dual-stack on 1panel-network by default.

Before

EnableIPv6: new(bool)  // pointer to false - IPv6 explicitly disabled

After

EnableIPv6: &enableIPv6  // true
IPAM: {
    Config: [
        {Subnet: "172.18.0.0/16", Gateway: "172.18.0.1"},       // IPv4
        {Subnet: "fd00:1panel::/64", Gateway: "fd00:1panel::1"}, // IPv6 ULA
    ]
}

Uses ULA (Unique Local Address) range fd00:1panel::/64 - no public IPv6 required, works for internal container networking.

Note: Only affects new installations or networks created after this change. Existing users need to recreate the network manually.

Changed file

• agent/utils/docker/docker.go (+8, -1)

feat: Enable IPv6 dual-stack support on 1panel-network by default (#12202)

[f2c-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
Once this PR has been reviewed and has the lgtm label, please assign wanghe-fit2cloud for approval. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Details

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment