thunderbird: support setting search engines

[kira-bruneau]

Description

• Splits firefox search engine configuration into a separate submodule so it can be reused in thunderbird
• Removes myself maintainer for all of firefox, and adds myself as a maintainer for just the search engine submodule

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

• Test cases updated/added. See example.

  Submodule already tested in firefox-profile-search tests.

• Commit messages are formatted like

  {component}: {description}
  
  {long description}
  

  See CONTRIBUTING for more information and recent commit messages for examples.

• If this PR adds a new module

  • Added myself as module maintainer. See example.

Maintainer CC

Firefox:
@rycee @brckd

Thunderbird:
@d-dervishi

[kira-bruneau]

I was also thinking of splitting out generating user.js & chrome from firefox so changes there would also be shared in thunderbird (see #3808, #5077, #5670), but decided to keep this focused on search for now to simplify the review.

[kira-bruneau]

I also just pushed a change that also organizes the firefox tests by submodule.

[kira-bruneau]

Actually, I just decided to split off test refactoring into it's own PR, because the change is easier to review separately: #5698

[brckd]

Thanks @kira-bruneau! No issues from my side, since it doesn't affect the functionality of the Firefox module. The formatting only conflicts with #5685 so far, which would become your responsibility when you become the maintainer of this module.

[kira-bruneau]

I added this internal enable option to make the implicit enable behaviour reusable, but I think ideally users should be required to set enable explicitly. I just didn't want to introduce any breaking changes here.

I plan on folding the force option into enable in a follow-up PR.

[khaneliman]

Getting this after this commit. Both files referenced with different definitions are the firefox module in home-manager.

error: The option `home-manager.users.khaneliman.home.file.".mozilla/firefox/khaneliman/search.json.mozlz4".enable' has conflicting definition values:
       - In `/nix/store/i9vkk0yd40vsvn73a1rfi60p2p0dhc8m-source/modules/programs/firefox.nix': true
       - In `/nix/store/i9vkk0yd40vsvn73a1rfi60p2p0dhc8m-source/modules/programs/firefox.nix': false

[teto]

before merging, I managed to rebuild firefox with custom search engines and started thunderbird (that I dont use ) fine hence the merge. I apaprently missed some stuff.

[khaneliman]

Hmm.. I can double check my config.. but I didn't spend too much time looking originally because both files referenced were an internal home-manager module.

[khaneliman]

Appears to be issue with multiple profiles sharing a path. One profile doesn't set the search option, the other uses it. This conflict is thrown.

      profiles = {
        "dev-edition-default" = {
          id = 0;
          path = "${config.${namespace}.user.name}";
        };

        ${config.${namespace}.user.name} = {
          inherit (cfg) extraConfig extensions search;
          inherit (config.${namespace}.user) name;