Ansible convert dictionary to mix of dictionary/array

I use following files: variable file: db.yml

x86_64:  
  alpine:
    version: 3.15.0
  debian:
    version: 11.3.0

aarch64:
  alpine:
    version: 3.15.0
  debian:
    version: 11.3.0

playbook: playbook.yml

---
- name: "Playbook" 
  hosts: localhost
  connection: local
  gather_facts: no

  tasks:
  - name: Import variables
    ansible.builtin.include_vars:
      file: db.yml
      name: db

  - name: DENUG >>> db
    debug:
      var: db


  - name: DENUG >>> db
    debug:
      var: db[item].alpine
    loop: "{{ db.keys()|list }}"
    when: db[item].alpine is defined

Output:

ok: [localhost] => (item=x86_64) => {
    "ansible_loop_var": "item",
    "db[item].alpine": {
        "version": "3.15.0"
    },
    "item": "x86_64"
}
ok: [localhost] => (item=aarch64) => {
    "ansible_loop_var": "item",
    "db[item].alpine": {
        "version": "3.15.0"
    },
    "item": "aarch64"
}

Now I have converted db.yml to new style as following:

x86_64:
  - distribution: alpine
    version: 3.15.0
  - distribution: debian
    version: 11.3.0

aarch64:
  - distribution: alpine
    version: 3.15.0
  - distribution: debian
    version: 11.3.0

Question:
How to run similar command as following:

- name: DENUG >>> db
    debug:
      var: db[item].alpine
    loop: "{{ db.keys()|list }}"
    when: db[item].alpine is defined

and get the same result as available in the output.
Basically how to loop through this new db.yml to get value for db.x86_64.alpine.version