refactor(Font): rename fontStore and appliedFontsManager

Both names were vague or overloaded:

- fontStore / FontStore -> fontCatalogStore / FontCatalogStore
  Three font-related stores live in this slice; the new name names the
  paginated catalog specifically.

- appliedFontsManager / AppliedFontsManager -> fontLifecycleManager /
  FontLifecycleManager
  "Applied" collided with the filter-side appliedFilterStore (different
  meaning). The class actually orchestrates a load-use-evict lifecycle
  with FontBufferCache + FontEvictionPolicy + FontLoadQueue
  collaborators, so "Manager" is justified. Companion types file moved
  alongside (appliedFonts.ts -> fontLifecycle.ts).

Directories, file basenames, factory (createFontStore ->
createFontCatalogStore), and the AppliedFontsManagerDeps interface all
renamed. All consumers (ComparisonView, SampleList, FontList,
FontApplicator, FontVirtualList, FilterAndSortFonts bindings,
createFontRowSizeResolver, mocks) updated.

src/widgets/ComparisonView/ui/Search/Search.svelte

@@ -2,7 +2,7 @@
     Component: Search
     Typeface search input for the comparison view.
     Writes through appliedFilterStore; the global bridge in $features/FilterAndSortFonts
-    propagates the value into fontStore.
+    propagates the value into fontCatalogStore.
 -->
 <script lang="ts">
 import { appliedFilterStore } from '$features/FilterAndSortFonts';