setup(ci): add markdown changes validation

Author: ArtemkaKun

.github/workflows/validate_new_changes.yml

@@ -4,13 +4,24 @@ on:
     pull_request:  # yamllint disable-line rule:empty-values
 
 jobs:
-    validate-new-changes:
+    validate-yaml-changes:
         runs-on: "ubuntu-latest"
-        # NOTE: validating new changes takes around 1 minute.
+        # NOTE: validating YAML changes takes around 1 minute.
         # If this job takes more than 5 minutes, it means that something is wrong.
         timeout-minutes: 5
         steps:
             - name: "Checkout ${{ github.event.repository.name }}"
               uses: "actions/checkout@v4"
             - name: "Run YAML linter"
               run: "docker run --rm -v ${{ github.workspace }}:/linter_workdir/repo spawnlang/yaml-linter:latest"
+
+    validate-markdown-changes:
+        runs-on: "ubuntu-latest"
+        # NOTE: validating Markdown changes takes around 1 minute.
+        # If this job takes more than 5 minutes, it means that something is wrong.
+        timeout-minutes: 5
+        steps:
+            - name: "Checkout ${{ github.event.repository.name }}"
+              uses: "actions/checkout@v4"
+            - name: "Run Markdown linter"
+              run: "docker run --rm -v ${{ github.workspace }}:/linter_workdir/repo spawnlang/markdown-linter:latest"

README.md

@@ -12,10 +12,10 @@ run, edit and share Spawn code online.
 - Ability to [run code as tests](https://docs.spawnlang.dev/tools/playground.html#test)
 - Ability to [see generated C code](https://docs.spawnlang.dev/tools/playground.html#show-generated-c-code)
   for passed Spawn code
-- Pass [flags](https://docs.spawnlang.dev/tools/playground.html#pass-arguments-to-compiler) to Spawn
-  compiler and binary
-- [Shareable](https://docs.spawnlang.dev/tools/playground.html#share-code) code and editor state
-  via URL or local storage
+- Pass [flags](https://docs.spawnlang.dev/tools/playground.html#pass-arguments-to-compiler)
+  to Spawn compiler and binary
+- [Shareable](https://docs.spawnlang.dev/tools/playground.html#share-code) code
+  and editor state via URL or local storage
 
 ## Developing
 
@@ -52,7 +52,8 @@ then access the playground at <http://localhost:5555>
 
 ## Server API
 
-See [server/README.md](./server/README.md) for more information about the server API.
+See [server/README.md](./server/README.md) for more information about the server
+API.
 
 ## License
 

server/README.md

@@ -56,7 +56,8 @@ Additional form fields:
 #### Request
 
 ```curl
-curl -X POST localhost:5555/run_test -F 'code="fn test_foo() { assert 100 == 100 }"'
+curl -X POST localhost:5555/run_test \
+-F 'code="fn test_foo() { assert 100 == 100 }"'
 ```
 
 #### Response