chore: bump version to 1.4.8, sync manifest

- csproj <Version>, Plugin.cs schema-gate self-reference, repo.json
  (AssemblyVersion, TestingAssemblyVersion, 3x DownloadLink URLs).
- README.md shield badge, version header, Project Status body.
- docs/CHANGELOG.md gains a v1.4.8 section above v1.4.7.
- docs/ROADMAP.md flips Next Cycle to v1.4.9 (Plugin-Load Render
  Polish), v1.4.8 moves into the released history above v1.4.7.
- Config schema stays at v17, Migration v17 stays additive.

repo.json Changelog field and HellionChat.yaml changelog block plus
the new forge-posts/v1.4.8.md follow in a separate commit (slim-drop
of v1.4.4 happens there).

docs/CHANGELOG.md

@@ -10,6 +10,35 @@ to the release pages for details.
 
 ---
 
+## Hellion Chat 1.4.8 — Hook-Layer and Polish Quick-Wins (2026-05-14)
+
+Ninth sub-patch of the v1.4.x polish-sweep series. Hook-layer cluster (FTS5 full-text search, ad-block foundation
+investigation) plus three polish quick-wins.
+
+- DbViewer full-text search: optional FTS5 index across the full chat history. Built asynchronously on first run after
+  the update with a progress toast (UI stays responsive, the toggle is disabled until the build completes). The local
+  page-filter remains the default mode. Multi-word queries match as exact phrases; power users can opt into raw FTS5
+  `MATCH` syntax by wrapping their own double-quotes around the term.
+- Custom theme files now auto-reload when edited while the theme is active. Save the JSON in your editor and the live
+  render picks up the change within a second — no need to re-click the theme in the picker. Disk-stat is throttled to
+  1 Hz so per-frame cost stays free.
+- Retention sweep no longer blocks the framework thread. `Framework.Run(...).Wait()` is replaced by
+  `Framework.RunOnTick(...)`, which removes the ~194 ms hitch the sweep used to add per run.
+- Status bar height is derived from `GetTextLineHeightWithSpacing()` plus a DPI-aware spacer so the bar renders
+  correctly at Windows display scaling above 100 %. Linux/Wayland default of 100 % is unaffected.
+- Receive-suppressed-tells routing was investigated this cycle and **postponed to v1.5.x**. When other plugins suppress
+  tells via `CheckMessageHandled`, FFXIV's chat pipeline skips the `RaptureLogModule.AddMsgSourceEntry` path, which means
+  HellionChat's `ContentIdResolverHook` does not fire and tell-partner identification breaks for AutoTellTab routing.
+  The proper fix sits next to the planned ad-block hook layer (`RaptureLogModule.ShowMiniTalkPlayer` and friends) where
+  the same patch surface comes up anyway.
+- Internal: storage form of `messages.Id` clarified (declared BLOB but Microsoft.Data.Sqlite stores Guid parameters as
+  TEXT). FTS bulk insert and `LoadByGuids` join now match the TEXT storage form on both sides. Migration v17 stays
+  (no schema bump).
+
+Based on Chat 2 1.35.3 (upstream Infiziert90/ChatTwo, EUPL-1.2).
+
+---
+
 ## Hellion Chat 1.4.7 — Backlog Cleanup and Mid-Features (2026-05-13)
 
 Eighth sub-patch of the v1.4.x polish-sweep series. First user-visible feature bundle since v1.4.5 — pinned tell tabs