docs: fix broken links and anchors across documentation

Fix ~30 broken links and anchors across the documentation site, including
incorrect relative paths, mismatched anchor names, zero-width characters
in URLs, and references to renamed or removed headings.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Signed-off-by: Fredrik Adelöw <freben@spotify.com>

docs/references/glossary.md

@@ -186,7 +186,7 @@ This standard is a key component of [OpenID Connect](#openid-connect-aka-oidc).
 
 Classification of an [entity](#entity) in the Backstage Software Catalog, for example _service_, _database_, or _team_. An element of the [kind|namespace|name triplet](#kind-namespace-name-triplet) that is an important concept for uniqueness.
 
-## Kind|namespace|name triplet
+## Kind|namespace|name triplet {#kind-namespace-name-triplet}
 
 The primary reference for [Software Catalog](#software-catalog) entities. It is human-readable and should be unique across your Backstage instance.
 
@@ -379,7 +379,7 @@ Existing search technology that [Backstage Search](#search) can take advantage o
 
 The Software Catalog is a core feature of Backstage. See [Backstage Software Catalog](https://backstage.io/docs/next/features/software-catalog/) for an overview, the life of an entity in the catalog, how to configure the catalog, its architecture and high-level design, how to configure and customize it, and its API. The overview describes how the catalog works, how to add components to it, how to find software in it, and more.
 
-## Software Templates (aka Scaffolder)
+## Software Templates (aka Scaffolder) {#software-templates}
 
 1. A "skeleton" software project created and managed in the Backstage Software Templates tool.