Update welcome text and add conditional for adding remote fork

.devcontainer/devcontainer.json

@@ -6,8 +6,5 @@
 	"onCreateCommand": "sudo cp .devcontainer/welcome-message.txt /usr/local/etc/vscode-dev-containers/first-run-notice.txt",
 
 	// Runs the initial setup commands after the container is created.
-	"postCreateCommand": "sudo chmod +x .devcontainer/post-create-command.sh && .devcontainer/post-create-command.sh",
-
-    // Activates the virtual environment after the container is started.
-	"postStartCommand": ". .venv/bin/activate"
+	"postCreateCommand": "sudo chmod +x .devcontainer/post-create-command.sh && .devcontainer/post-create-command.sh"
 }

.devcontainer/post-create-command.sh

@@ -3,7 +3,9 @@ set -e
 
 # Add user's fork as a remote
 GIT_USER=$(git config user.name)
-git remote add fork https://github.com/${GIT_USER}/flask
+if [ ! git remote | grep -q "fork" ]; then
+    git remote add fork https://github.com/${GIT_USER}/flask
+fi
 
 # Create and activate a virtualenv
 python3 -m venv .venv
@@ -11,16 +13,10 @@ python3 -m venv .venv
 
 # Upgrade pip and setuptools
 python -m pip install --upgrade pip setuptools
-echo "Upgraded setuptools"
 
 # Install the development dependencies, then install Flask in editable mode
 pip install -r requirements/dev.txt && pip install -e .
-echo "Installed dependencies and Flask"
 
-# Install pre-commit hooks
+# Install pre-commit hooks and coverage
 pre-commit install
-echo "Installed pre-commit hooks"
-
-# Install coverage
 pip install coverage
-echo "Installed coverage"

.devcontainer/welcome-message.txt

@@ -2,6 +2,8 @@
 
 🛠️  Your environment is setup with all the required dependencies and your fork has been added as a remote.
 
-📝  Wait for the "postCreateCommand" to finish setting things up, then run `. .venv/bin/activate` to activate your virtualenv.
+📝  Wait for the "postCreateCommand" to finish setting things up.
 
-🚀  To start coding, checkout a branch from the latest release for bugs or docs fixes, or from main for new feature work.
+🚀  To start coding:
+    - run `. .venv/bin/activate` to activate your virtualenv
+    - run `git checkout -b your-branch-name origin/{main-or-latest-release}` to start working on a new feature or bug fix