fix: restore canonical .markdownlint.json + .editorconfig

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false

.markdownlint.json

@@ -0,0 +1,8 @@
+{
+  "default": true,
+  "MD013": false,
+  "MD033": false,
+  "MD041": false,
+  "MD060": false,
+  "MD024": { "siblings_only": true }
+}

CHANGELOG.md

@@ -7,6 +7,7 @@ All notable changes to this project are documented here. Format based on [Keep a
 ### Added
 
 - `README.md` — quick-start, sovereignty sequence summary, file map.
+- `.markdownlint.json` and `.editorconfig` from the WorldRover canon. Initial scaffold missed these; CI was red on default markdownlint MD013 (line-length) until the configs landed. Plus a local `MD024: {siblings_only: true}` override so the standard Keep a Changelog repeated `### Added` headings under different version sections don't trigger duplicate-heading errors. Closes #1.
 
 ## [0.1.0] - 2026-04-26