v2.8.6

Code Refactoring

• restructure files (#1613) #1613 (Randy Lai)

Chores

• update changelog (Randy Lai)
• fix markdownlint (Randy Lai)

Commits

• b0781fe: improve R syntax highlight (#1605) (Randy Lai) #1605
• cc3f2f2: Show sidebar icon only when extension is active (#1579) (Clemens Brunner) #1579
• 2d11589: Move R and R markdown syntaxes to vscode-R-syntax (#1606) (Randy Lai) #1606