Add BluditGithubImport class for GitHub article import functionality

- Implemented methods for slug validation, path validation, scalar parsing, and document processing.
- Added link and image handling with safety checks for content.
- Introduced blob verification for GitHub responses and asset type validation.
- Created unit tests for the import functionality, covering various edge cases and ensuring robust error handling.
- Included tests for metadata preservation, asset handling, and concurrent edits.

metadata.json

@@ -1,10 +1,10 @@
 {
-	"author": "spleenftw",
-	"email": "",
-	"website": "https://github.com/interlope/bludit-github",
-	"version": "1.0.0",
-	"releaseDate": "2026-06-01",
-	"license": "MIT",
-	"compatible": "3.22.0",
-	"notes": "Export Bludit articles to a GitHub repository as Markdown files with YAML frontmatter."
+  "author": "spleenftw",
+  "email": "",
+  "website": "https://github.com/Spleenftw/bludit-github-sync",
+  "version": "1.1.0",
+  "releaseDate": "2026-11-01",
+  "license": "MIT",
+  "compatible": "3.22.0",
+  "notes": "Export Bludit articles to GitHub and preview/import selected articles, metadata, images and attachments back into Bludit."
 }