How to recognize the need to reset the Apex DB.

[peternhale]

The Apex language server can run into terminal errors or be unable to service a request.

• The language server failing to start can be identified by a failed status bar item.

• If the server seems to hang, examine the Apex language server output channel for stack traces.

• To resolve this, reset the ./sfdx/tools directory by running "SFDX: Restart Apex Language Server" and selecting "Clean Apex DB and Restart," or manually deleting the .sfdx/tools folder and reloading VS Code.