feat: limit use of IFD, add auto updates & vm testing (#40)

* feat(modules): remove unnecessary IFD

by moving all upstream repos to our flake inputs, we no longer need
to have [IFD](https://nixos.wiki/wiki/Import_From_Derivation) in most
of our modules - making evaluation faster for all configurations. the
only remaining instances of IFD are in `lib.ctp.toYAML` and the themes
for kitty, which is due to it's use upstream in home-manager

* ci: start auto updating flake inputs

* ci: init basic vm tests

* ci: rename ci to format

* ci: use PAT for update-lock workflow

this is required to run tests such as test-vm after the pull request is
made

* fix(home-manager): make sure to use readFile in helix module

* ci: fix typo in test-vm

* ci: use verbose logging in test-vm & enable kvm

* docs: add flake inputs & vm testing to CONTRIBUTING.md

* feat(modules)!: use nvfetcher for upstream sources

* docs: add information about nvfetcher

* chore: don't include flake-compat in flake inputs

while this does make us lose out on easy updating, i think it's nice not
  have this as a required dependency for flake users

* chore: update flake inputs

Flake lock file updates:

• Updated input 'home-manager':
    'github:nix-community/home-manager/f58889c07efa8e1328fdf93dc1796ec2a5c47f38' (2023-07-29)
  → 'github:nix-community/home-manager/48b0a30202516e25d9885525fbb200a045f23f26' (2023-11-01)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/2a9d660ff0f7ffde9d73be328ee6e6f10ef66b28' (2023-07-28)
  → 'github:NixOS/nixpkgs/0cbe9f69c234a7700596e943bfae7ef27a31b735' (2023-10-29)

* chore: update nvfetcher sources

* refactor: don't instantiate nixpkgs in flake + cleanup vm test

* fix(home-manager): update paths from new lazygit theme revision

* feat(lib)!: use constant module arguments automatically

.github/workflows/ci.yml → .github/workflows/format.yml

@@ -1,11 +1,11 @@
-name: CI
+name: Format
 
 on:
   - push
   - pull_request
 
 jobs:
-  Check:
+  format-check:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2

.github/workflows/test-vm.yml

@@ -0,0 +1,28 @@
+name: Test modules
+
+on:
+  push:
+    paths:
+      - 'modules/**'
+      - 'test.nix'
+      - 'flake.*'
+  pull_request:
+    paths:
+      - 'modules/**'
+      - 'test.nix'
+      - 'flake.*'
+  workflow_dispatch:
+
+jobs:
+  run-vm:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: cachix/install-nix-action@v20
+        with:
+          extra_nix_config: "system-features = benchmark big-parallel kvm nixos-test uid-range"
+      - uses: DeterminateSystems/magic-nix-cache-action@main
+
+      - name: Run VM
+        run: nix build -Lv .#checks.x86_64-linux.module-vm-test

.github/workflows/update-lock.yml

@@ -0,0 +1,41 @@
+name: Update lockfiles
+
+on:
+  schedule:
+    # run every friday
+    - cron: "0 0 * * 5"
+  workflow_dispatch:
+
+jobs:
+  update-locks:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v22
+
+      - name: Set Git user info
+        run: |
+          git config user.name 'github-actions[bot]'
+          git config user.email 'github-actions[bot]@users.noreply.github.com'
+
+      - name: Update flake inputs
+        run: |
+          nix flake update \
+            --commit-lock-file --commit-lockfile-summary "chore: update flake inputs"
+
+      - name: Update upstream sources
+        run: |
+          nix run nixpkgs#nvfetcher
+
+      - name: Create PR
+        uses: peter-evans/create-pull-request@v5
+        with:
+          token: ${{ secrets.LOCKFILE_TOKEN }}
+          base: "main"
+          branch: "update-lock"
+          delete-branch: true
+          committer: github-actions[bot] github-actions[bot]@users.noreply.github.com
+          commit-message: "chore: update nvfetcher sources"
+          title: "chore: update lockfiles"
+          body: "Automated pull request updating flake inputs and nvfetcher sources"

CONTRIBUTING.md

@@ -8,6 +8,20 @@ Create a file in `modules/<module>/` with the name of the port. Add the file to
 `catppuccin.accent` option. `catppuccin.flavour` and `catppuccin.accent` should
 default to `config.catppuccin.flavour` and `config.catppuccin.accent`, respectively.
 
+[nvfetcher](https://github.com/berberman/nvfetcher) is used to track our upstream
+sources to use in modules. This allows us to reduce [IFD](https://nixos.wiki/wiki/Import_From_Derivation)
+and auto-update all themes. Most repositories can be specified like so:
+
+```toml
+[program_name]
+src.git = "https://github.com/catppuccin/program_name.git"
+fetch.github = "catppuccin/program_name"
+```
+
+After creating your module, add the options to enable it in `test.nix` under the
+`nodes.machine` attrset. This will allow for your configuration to be tested along
+with the other modules in a VM automatically.
+
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