changelog: prepare v0.84.0 release

Summarise changes merged since v0.83.0:
- Fix SourceLink go-to-def on .NET 10 Linux (#1441)
- Add backgroundServiceProgress config option (#1452)
- Fix { trigger char for interpolated strings (#1454)
- Fix non-ASCII URI encoding (#1455)
- Fix spurious get/set rename (#1453)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 2 people

CHANGELOG.md

@@ -1,5 +1,18 @@
 # Changelog
 
+## [0.84.0] - 2026-02-23
+
+### Added
+
+- [Add `FSharp.notifications.backgroundServiceProgress` config option to suppress background analyzer progress notifications](https://github.com/ionide/FsAutoComplete/pull/1452)
+
+### Fixed
+
+- [Fix SourceLink go-to-definition failure when .NET 10 is used on Linux](https://github.com/ionide/FsAutoComplete/pull/1441) (thanks @serefarikan!)
+- [Fix missing `{` completion trigger character for interpolated string expressions](https://github.com/ionide/FsAutoComplete/pull/1454)
+- [Fix non-ASCII path characters encoded incorrectly in file URIs](https://github.com/ionide/FsAutoComplete/pull/1455)
+- [Fix spurious rename of `get`/`set` accessor keywords when renaming a property](https://github.com/ionide/FsAutoComplete/pull/1453)
+
 ## [0.83.0] - 2026-02-04
 
 ### Added