Move the header id tracking into the renderer context rather than a global state. Since the RendererContext is
initialized for each execution of the marked parser, we can store the context of which header ids have been seen within
a single page there which allows us to run these parse interactions in parallel.
(cherry picked from commit a16a70ca74)
Improves the symbol linking logic to handle Angular component selectors (e.g., ngCombobox). It attempts to convert Angular selector patterns to their corresponding class names, improving navigation to Angular API documentation.
(cherry picked from commit 2d854e01bc)
Extends the Markdown parser to support `loading`, `decoding`, and `fetchpriority` attributes for images via curly brace syntax.
(cherry picked from commit 46269be842)
Adds a new landing page for developer events, starting with the v21 page. It also includes an ICS file link for calendar invites. Also updated the tests for the docs-pill to support two new attributes so developers can add the event to their calendars.
(cherry picked from commit 7a422c209a)
