build: modernize repository (#27)

* build: clean up gitignore and remove empty gitmodules

Problem: .gitignore contained 48 lines of C/shared-object boilerplate
irrelevant to a Lua Neovim plugin. .gitmodules was tracked but empty.

Solution: replace .gitignore with minimal entries covering only files
this project actually produces. Delete the vestigial .gitmodules.

* build: add editorconfig and prettierrc

Problem: no editor or formatter configuration, inconsistent with
cp.nvim and diffs.nvim conventions.

Solution: add .editorconfig (2-space Lua indent, utf-8, final newline)
and .prettierrc (prose wrap, 80 cols, single quotes, no semi) matching
the other repos.

* build: add Makefile for lint and test targets

Problem: .github/pre-commit calls `make fastlint` and .github/pre-push
calls `make lint && make test`, but no Makefile existed, so the git
hooks failed.

Solution: add Makefile with lint (stylua + selene), fastlint
(pre-commit), and test (luarocks test) targets.

* docs: add fork copyright to LICENSE

Problem: LICENSE only contained the original author's copyright notice.

Solution: add a second copyright line for the fork maintainer. MIT
requires retaining the original notice; adding a line for derivative
work is standard practice.

* ci: restructure workflows to quality/test/luarocks pattern

Problem: CI used a single tests.yml for linting, typechecking, and
testing. No conditional path filtering, no markdown format check, and
a stale mirror_upstream_prs.yml and duplicate luarocks.yml existed.

Solution: replace tests.yml with quality.yaml (stylua, selene,
lua-typecheck, prettier with dorny/paths-filter) and test.yaml
(nvim-busted, stable+nightly matrix). Update luarocks.yaml to
reference quality.yaml. Delete mirror_upstream_prs.yml and duplicate
luarocks.yml. Fix automation workflow sender check.

* build: rewrite issue templates

Problem: issue templates used upstream stevearc references, severity
dropdowns, outdated lazy.nvim bootstrap, and the .yml extension
inconsistent with other repos.

Solution: replace with .yaml templates matching cp.nvim/diffs.nvim
style. Bug report uses prerequisites checkboxes, checkhealth output,
modern lazy.nvim bootstrap with vim.g.oil pattern. Feature request
uses problem/solution/alternatives format. Add config.yaml to disable
blank issues and link discussions.

* docs: rewrite README

Problem: README contained upstream triage tables, severity dropdowns,
the old setup() pattern, a tree view question, and references to
stevearc/oil.nvim as the primary source.

Solution: full rewrite matching cp.nvim/diffs.nvim style with bold
tagline, features list, requirements, installation, documentation,
FAQ (lazy.nvim setup with vim.g.oil, migration guide, alternatives),
and acknowledgements crediting the original author.

* revert: remove Makefile

Problem: Makefile was added in b9279b5 but was previously deleted
intentionally.

Solution: remove it.

.github/workflows/automation_remove_question_label_on_comment.yml

@@ -8,7 +8,7 @@ jobs:
   # issues in my "needs triage" filter.
   remove_question:
     runs-on: ubuntu-latest
-    if: github.event.sender.login != 'stevearc'
+    if: github.event.sender.login != 'barrettruth'
     steps:
       - uses: actions/checkout@v4
       - uses: actions-ecosystem/action-remove-labels@v1

.github/workflows/luarocks.yaml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   quality:
-    uses: ./.github/workflows/tests.yml
+    uses: ./.github/workflows/quality.yaml
 
   publish:
     needs: quality

.github/workflows/luarocks.yml

@@ -1,21 +0,0 @@
-name: luarocks
-
-on:
-  push:
-    tags:
-      - 'v*'
-
-jobs:
-  tests:
-    uses: ./.github/workflows/tests.yml
-
-  publish:
-    needs: tests
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: nvim-neorocks/luarocks-tag-release@v7
-        env:
-          LUAROCKS_API_KEY: ${{ secrets.LUAROCKS_API_KEY }}

.github/workflows/mirror_upstream_prs.yml

@@ -1,85 +0,0 @@
-name: Mirror Upstream PRs
-on:
-  schedule:
-    - cron: "0 8 * * *"
-  workflow_dispatch:
-
-permissions:
-  issues: write
-
-jobs:
-  mirror:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Mirror new upstream PRs
-        uses: actions/github-script@v7
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          script: |
-            const upstream = { owner: 'stevearc', repo: 'oil.nvim' };
-            const fork = { owner: 'barrettruth', repo: 'oil.nvim' };
-
-            const since = new Date();
-            since.setDate(since.getDate() - 1);
-            const sinceISO = since.toISOString();
-
-            const { data: prs } = await github.rest.pulls.list({
-              ...upstream,
-              state: 'open',
-              sort: 'created',
-              direction: 'desc',
-              per_page: 30,
-            });
-
-            const recentPRs = prs.filter(pr => {
-              if (new Date(pr.created_at) < since) return false;
-              if (pr.user.login === 'dependabot[bot]') return false;
-              if (pr.user.login === 'dependabot-preview[bot]') return false;
-              return true;
-            });
-
-            if (recentPRs.length === 0) {
-              console.log('No new upstream PRs in the last 24 hours.');
-              return;
-            }
-
-            const { data: existingIssues } = await github.rest.issues.listForRepo({
-              ...fork,
-              state: 'all',
-              labels: 'upstream/pr',
-              per_page: 100,
-            });
-
-            const mirroredNumbers = new Set();
-            for (const issue of existingIssues) {
-              const match = issue.title.match(/^upstream#(\d+)/);
-              if (match) mirroredNumbers.add(parseInt(match[1]));
-            }
-
-            for (const pr of recentPRs) {
-              if (mirroredNumbers.has(pr.number)) {
-                console.log(`Skipping PR #${pr.number} — already mirrored.`);
-                continue;
-              }
-
-              const labels = pr.labels.map(l => l.name).join(', ') || 'none';
-
-              await github.rest.issues.create({
-                ...fork,
-                title: `upstream#${pr.number}: ${pr.title}`,
-                body: [
-                  `Mirrored from [stevearc/oil.nvim#${pr.number}](${pr.html_url}).`,
-                  '',
-                  `**Author:** @${pr.user.login}`,
-                  `**Labels:** ${labels}`,
-                  `**Created:** ${pr.created_at}`,
-                  '',
-                  '---',
-                  '',
-                  pr.body || '*No description provided.*',
-                ].join('\n'),
-                labels: ['upstream/pr'],
-              });
-
-              console.log(`Created issue for upstream PR #${pr.number}: ${pr.title}`);
-            }

.github/workflows/quality.yaml

@@ -0,0 +1,90 @@
+name: quality
+
+on:
+  workflow_call:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  changes:
+    runs-on: ubuntu-latest
+    outputs:
+      lua: ${{ steps.changes.outputs.lua }}
+      markdown: ${{ steps.changes.outputs.markdown }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dorny/paths-filter@v3
+        id: changes
+        with:
+          filters: |
+            lua:
+              - 'lua/**'
+              - 'plugin/**'
+              - 'spec/**'
+              - '*.lua'
+              - '.luarc.json'
+              - '*.toml'
+            markdown:
+              - '*.md'
+
+  lua-format:
+    name: Lua Format Check
+    runs-on: ubuntu-latest
+    needs: changes
+    if: ${{ needs.changes.outputs.lua == 'true' }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: JohnnyMorganz/stylua-action@v4
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          version: 2.1.0
+          args: --check lua spec
+
+  lua-lint:
+    name: Lua Lint Check
+    runs-on: ubuntu-latest
+    needs: changes
+    if: ${{ needs.changes.outputs.lua == 'true' }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Lint with Selene
+        uses: NTBBloodbath/selene-action@v1.0.0
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          args: --display-style quiet .
+
+  lua-typecheck:
+    name: Lua Type Check
+    runs-on: ubuntu-latest
+    needs: changes
+    if: ${{ needs.changes.outputs.lua == 'true' }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Run Lua LS Type Check
+        uses: mrcjkb/lua-typecheck-action@v0
+        with:
+          checklevel: Warning
+          directories: lua
+          configpath: .luarc.json
+
+  markdown-format:
+    name: Markdown Format Check
+    runs-on: ubuntu-latest
+    needs: changes
+    if: ${{ needs.changes.outputs.markdown == 'true' }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 8
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+      - name: Install prettier
+        run: pnpm add -g prettier@3.1.0
+      - name: Check markdown formatting with prettier
+        run: prettier --check .

.github/workflows/test.yaml

@@ -0,0 +1,22 @@
+name: test
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        nvim: [stable, nightly]
+    name: Test (Neovim ${{ matrix.nvim }})
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: nvim-neorocks/nvim-busted-action@v1
+        with:
+          nvim_version: ${{ matrix.nvim }}

.github/workflows/tests.yml

@@ -1,60 +0,0 @@
-name: Tests
-
-on:
-  workflow_call:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches:
-      - main
-
-jobs:
-  selene:
-    name: Selene
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: NTBBloodbath/selene-action@v1.0.0
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          args: --display-style quiet .
-
-  stylua:
-    name: StyLua
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Stylua
-        uses: JohnnyMorganz/stylua-action@v4
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          version: v2.1.0
-          args: --check lua spec
-
-  typecheck:
-    name: typecheck
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: mrcjkb/lua-typecheck-action@v0
-        with:
-          checklevel: Warning
-          directories: lua
-          configpath: .luarc.json
-
-  run_tests:
-    strategy:
-      fail-fast: false
-      matrix:
-        nvim_version:
-          - stable
-          - nightly
-
-    name: Run tests
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: nvim-neorocks/nvim-busted-action@v1
-        with:
-          nvim_version: ${{ matrix.nvim_version }}