docs: update changelog and plugin history for v0.9.2 release

Add entries for PRs #838, #839, and #840 covering deprecated API
replacements, plugin verifier fixes, and Kotlin K2 mode declaration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: stephanj

CHANGELOG.md

@@ -18,6 +18,10 @@ All notable changes to this project will be documented in this file.
 - Issue #809: Fix LM Studio API URL compatibility - changed default from `http://localhost:1234/api/v1/` to `http://localhost:1234/v1/` to match OpenAI-compatible chat completions endpoint, while preserving rich metadata endpoint access for context length detection
 - Issue #809: Fix LM Studio context length detection so model metadata no longer defaults to 8K when larger context values are available
 - Issue #809: Add optional LM Studio fallback context setting in the GUI when model metadata does not expose context length
+- Replace deprecated `Project.getBaseDir()` with `ProjectUtil.guessProjectDir()` across all scanner extensions (#838)
+- Replace deprecated `NioEventLoopGroup` with `MultiThreadIoEventLoopGroup` + `NioIoHandler` for Netty 4.2.x compatibility (#839)
+- Resolve plugin verifier warnings for experimental and deprecated API usage (#840)
+- Add Kotlin K2 plugin mode declaration (`supportsKotlinPluginMode`) in plugin.xml, required since IntelliJ 2024.2.1 (#840)
 
 ## [0.9.1]
 

src/main/resources/META-INF/plugin.xml

@@ -45,6 +45,10 @@
             <LI>Update welcome wording to Skills terminology and highlight MCP Marketplace first</LI>
             <LI>Issue #809: Fix LM Studio context length detection to use model metadata instead of defaulting to 8K</LI>
             <LI>Issue #809: Add optional LM Studio fallback context setting in the GUI</LI>
+            <LI>Replace deprecated Project.getBaseDir() with ProjectUtil.guessProjectDir()</LI>
+            <LI>Replace deprecated NioEventLoopGroup with MultiThreadIoEventLoopGroup for Netty 4.2.x</LI>
+            <LI>Resolve plugin verifier warnings for experimental and deprecated API usage</LI>
+            <LI>Add Kotlin K2 plugin mode declaration (supportsKotlinPluginMode)</LI>
         </UL>
         <h2>v0.9.1</h2>
         <UL>