feat(dock): migrate to treeland foreign toplevel manager v3 - #1789

On December 2, 2026, GitHub will restrict `pull_request_target` on public repositories by default. To continue allowing the event trigger, configure an Actions policy. Learn more: https://gh.io/securely-using-pull_request_target#default-policy-for-pull_request_target

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/setup-go@v3. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Include file: <sys/types.h> not found. Please note: Cppcheck does not need standard library headers to get proper results.

Include file: <cstdint> not found. Please note: Cppcheck does not need standard library headers to get proper results.

Include file: "qwayland-treeland-foreign-toplevel-manager-unstable-v3.h" not found.

The function 'treeland_foreign_toplevel_handle_v3_closed' is never used.

The function 'treeland_foreign_toplevel_handle_v3_done' is never used.

The function 'treeland_foreign_toplevel_handle_v3_state' is never used.

The function 'treeland_foreign_toplevel_handle_v3_identifier' is never used.

The function 'treeland_foreign_toplevel_handle_v3_app_id' is never used.

The function 'treeland_foreign_toplevel_handle_v3_title' is never used.

The function 'treeland_foreign_toplevel_handle_v3_pid' is never used.