Bump devcontainer image version

- Bump image version
- Add Ballerina toml and gitignore files

.devcontainer/devcontainer.json

@@ -5,13 +5,13 @@
 	"build": {
 		"dockerfile": "Dockerfile",
 		// Update 'VARIANT' to pick a Ballerina version
-		"args": { "VARIANT": "swan-lake-beta6" }
+		"args": { "VARIANT": "swan-lake-beta6-r4" }
 	},
 
 	// Set *default* container specific settings.json values on container create.
-	"settings": { 
-		"terminal.integrated.shell.linux": "/bin/bash"
-	},
+	// "settings": { 
+	// 	"terminal.integrated.shell.linux": "/bin/bash"
+	// },
 
 	// Add the IDs of extensions you want installed when the container is created.
 	"extensions": [
@@ -20,11 +20,16 @@
 	],
 
 	// Use 'forwardPorts' to make a list of ports inside the container available locally.
-	"forwardPorts": [8080],
+	// "forwardPorts": [8080],
 
-	// Use 'postCreateCommand' to run commands after the container is created.
-	// "postCreateCommand": "uname -a",
+	"initializeCommand": "mkdir -pv ./.ballerina",
+	"mounts": [
+		"type=bind,source=${localWorkspaceFolder}/.ballerina/,target=/home/vscode/.ballerina"
+	],
 
+	// Use 'postCreateCommand' to run commands after the container is created.
+	// "postCreateCommand": "",
+
 	// Comment out connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
 	"remoteUser": "vscode"
-}
+}

.gitignore

@@ -0,0 +1,3 @@
+.ballerina
+
+target

Ballerina.toml

@@ -0,0 +1,5 @@
+[package]
+distribution = "slbeta6"
+
+[build-options]
+observabilityIncluded = true