Pull request 2073: add-contributing

Squashed commit of the following:

commit 61dc1b63fe8ec124fa9a600a39a5e6b31ca91643
Merge: e6dc270b3 f44faa9be
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Nov 14 17:01:07 2023 +0300

    Merge branch 'master' into add-contributing

commit e6dc270b3f39445589fea5772f5c13183c1692fb
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Nov 13 13:43:59 2023 +0300

    all: add contributing

.github/PULL_REQUEST_TEMPLATE

@@ -1,7 +1,8 @@
 Before submitting a PR please make sure that:
 
 1.  You have discussed your solution in an issue and have got an
-    approval from a maintainer.
+    approval from a maintainer.  See our
+    [contribution guide](https://github.com/AdguardTeam/AdGuardHome/blob/master/CONTRIBUTING.md).
 
 2.  This isn't a localization fix; please send those to our
     [CrowdIn](https://crowdin.com/project/adguard-applications/en#/adguard-home)
@@ -13,8 +14,8 @@ Before submitting a PR please make sure that:
 Add a short description here.  The description should include:
 
 1.  Which issue this PR closes (`Closes #NNNN.`) or updates (`Updates
-    #NNNN.`).
+    #NNNN.`).  Please do not open PRs without filing an issue first.
 
 2.  A short description of how the change achieves that.
 
-Do not forget to remove these instructions.
+Do not forget to remove these instructions!

CONTRIBUTING.md

@@ -0,0 +1,89 @@
+ #  Contributing to AdGuard Home
+
+If you want to contribute to AdGuard Home by filing or commenting on an issue or
+opening a pull request, please follow the instructions below.
+
+
+
+##  General recommendations
+
+Please don't:
+
+ *  post comments like “+1” or “this”.  Use the :+1: reaction on the issue
+    instead, as this allows us to actually see the level of support for issues.
+
+ *  file issues about localization errors or send localization updates as PRs.
+    We're using [CrowdIn] to manage our translations and we generally update
+    them before each Beta and Release build.  You can learn more about
+    translating AdGuard products [in our Knowledge Base][kb-trans].
+
+ *  file issues about a particular filtering-rule list misbehaving.  These are
+    tracked through the [separate form for filtering issues][form].
+
+ *  send updates to filtering-rule lists, such as the ones for the Blocked
+    Services feature or the list of approved filtering-rule lists.  We update
+    them once before each Beta and Release build.
+
+Please do:
+
+ *  follow the template instructions and provide data for reproducing issues.
+
+ *  write the title of your issue or pull request in English.  Any language is
+    fine in the body, but it is important to keep the title in English to make
+    it easier for people and bots to look up duplicated issues.
+
+[CrowdIn]:  https://crowdin.com/project/adguard-applications/en#/adguard-home
+[form]:     https://link.adtidy.org/forward.html?action=report&app=home&from=github
+[kb-trans]: https://kb.adguard.com/en/general/adguard-translations
+
+
+
+##  Issues
+
+   ###  Search first
+
+Please make sure that the issue is not a duplicate or a question.  If it's a
+duplicate, please react to the original issue with a thumbs up.  If it's a
+question, please look through our [Wiki] and, if you haven't found the answer,
+post it to the GitHub [Discussions] page.
+
+[Discussions]: https://github.com/AdguardTeam/AdGuardHome/discussions/categories/q-a
+[Wiki]:        https://github.com/AdguardTeam/AdGuardHome/wiki
+
+
+
+   ###  Follow the issue template
+
+Developers need to be able to reproduce the faulty behavior in order to fix an
+issue, so please make sure that you follow the instructions in the issue
+template carefully.
+
+
+
+##  Pull requests
+
+   ###  Discuss your changes first
+
+Please discuss your changes by opening an issue.  The maintainers should
+evaluate your proposal, and it's generally better if that's done before any code
+is written.
+
+
+
+   ###  Review your changes for style
+
+We have a set of [code guidelines][hacking] that we expect the code to follow.
+Please make sure you follow it.
+
+[hacking]: https://github.com/AdguardTeam/CodeGuidelines/blob/master/Go/Go.md
+
+
+
+   ###  Test your changes
+
+Make sure that it passes linters and tests by running the corresponding Make
+targets.  For backend changes, it's `make go-check`.  For frontend, run
+`make js-lint`.
+
+Additionally, a manual test is often required.  While we're constantly working
+on improving our test suites, they're still not as good as we'd like them to be.