Merge pull request #20 from missingbulb/claude/vibrant-brahmagupta-4uhuwk

Add RESOURCES.md with external reference links

Author: missingbulb

RESOURCES.md

@@ -0,0 +1,17 @@
+# Resources
+
+Links to external references relevant to this project. When working on
+related features, check whether these pages contain useful details.
+
+- [Build a Google Calendar link](https://sadev.co.za/build-google-calendar-link) —
+  Explains the `calendar/render?action=TEMPLATE` URL parameters this
+  extension uses to pre-fill events.
+- [List of tz database time zones](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) —
+  Reference table of IANA timezone names, useful for parsing and
+  converting event date/time offsets.
+- [Kalinka](https://kalinka.tardate.com/) —
+  A bookmarklet/tool for adding web page events to Google Calendar,
+  similar in purpose to this extension.
+- [Stack Overflow: create a link to add a calendar entry](https://stackoverflow.com/questions/5831877/how-do-i-create-a-link-to-add-an-entry-to-a-calendar) —
+  Discussion of generating add-to-calendar links for Google, Outlook,
+  and other providers.