Cache prompt repo clones in a volume (#20)

* Cache prompt repo clones in a volume

Use a volume mount to cache the prompt repos between clones

* Fixes automatic pull of vonwig/prompts

The default value of promptImage will normally be tagged with latest
so this code was not doing anything.

src/utils/preparePrompt.ts

@@ -5,7 +5,7 @@ type PromptTypes = [{ title: string, type: string }];
 
 export const getPromptTypes = function (): PromptTypes {
     const promptImage = vscode.workspace.getConfiguration('docker.make-runbook').get('prompt-image') as string;
-    if (promptImage === "vonwig/prompts") {
+    if (promptImage === "vonwig/prompts" || promptImage === "vonwig/prompts:latest") {
         spawnSync('docker', ['pull', "vonwig/prompts"]);
     }
     const result = spawnSync('docker', ['run', '--rm', promptImage, "prompts"]);
@@ -18,7 +18,7 @@ export const prepareProjectPrompt = (projectRoot: vscode.WorkspaceFolder, userna
 
     const promptImage = vscode.workspace.getConfiguration('docker.make-runbook').get('prompt-image') as string;
 
-    const result = spawnSync('docker', ['run', '--rm', "-v", "/var/run/docker.sock:/var/run/docker.sock", promptImage, projectRoot.uri.fsPath, username, platform, promptType]);
+    const result = spawnSync('docker', ['run', '--rm', "-v", "/var/run/docker.sock:/var/run/docker.sock", "--mount", "type=volume,source=docker-prompts,target=/prompts", promptImage, projectRoot.uri.fsPath, username, platform, promptType]);
 
     if (result.error) {
         throw result.error;