docs: restructure documentation into MkDocs Material site

docs/reference/api/config.md

@@ -0,0 +1,12 @@
+# Config API
+
+Auto-generated reference for the [`Config`][unshackle.core.config.Config] object that models the
+`unshackle` configuration file. For a human-friendly walkthrough of every key, see the
+[Configuration Reference](../configuration.md).
+
+::: unshackle.core.config
+    options:
+      show_root_heading: false
+      show_source: false
+      members_order: source
+      heading_level: 2

docs/reference/api/drm.md

@@ -0,0 +1,13 @@
+# DRM API
+
+Auto-generated reference for the DRM systems: Widevine, PlayReady, ClearKey, and related helpers.
+For configuring DRM as a user, see [DRM & CDM Setup](../../guide/drm-and-cdm.md).
+
+::: unshackle.core.drm
+    options:
+      show_root_heading: false
+      show_source: false
+      members_order: source
+      heading_level: 2
+      filters:
+        - "!^_"

docs/reference/api/service.md

@@ -0,0 +1,12 @@
+# Service API
+
+Auto-generated reference for the [`Service`][unshackle.core.service.Service] base class that every
+service plugin subclasses. See [Creating a Service](../../dev/creating-a-service.md) for a guided
+walkthrough and [Service Architecture](../../dev/service-architecture.md) for the wider object model.
+
+::: unshackle.core.service
+    options:
+      show_root_heading: false
+      show_source: true
+      members_order: source
+      heading_level: 2

docs/reference/api/titles.md

@@ -0,0 +1,14 @@
+# Titles API
+
+Auto-generated reference for the title model: Movies, Series/Episodes, and Music/Albums/Songs.
+A service returns one of these collections from its title lookup. See
+[Creating a Service](../../dev/creating-a-service.md).
+
+::: unshackle.core.titles
+    options:
+      show_root_heading: false
+      show_source: false
+      members_order: source
+      heading_level: 2
+      filters:
+        - "!^_"

docs/reference/api/tracks.md

@@ -0,0 +1,14 @@
+# Tracks API
+
+Auto-generated reference for the track model: [`Tracks`][unshackle.core.tracks.Tracks],
+[`Track`][unshackle.core.tracks.Track], and the media-specific subclasses. See
+[Service Architecture](../../dev/service-architecture.md) for how these fit together.
+
+::: unshackle.core.tracks
+    options:
+      show_root_heading: false
+      show_source: false
+      members_order: source
+      heading_level: 2
+      filters:
+        - "!^_"