refactor(env): use lowercase var for root dir and improve venv activation

Refactored .source.dev to use a lowercase variable name for the root
directory path for consistency with shell conventions. Improved the
Poetry virtual environment activation by sourcing the activate script
directly.
No functional changes to environment setup logic.

Author: mkoura

.source.dev

@@ -16,12 +16,12 @@
 # export GITHUB_TOKEN=ghp_....
 INSTANCE_NUM="${INSTANCE_NUM:-0}"
 
-_ROOT_DIR_CNT="$(readlink -m "${BASH_SOURCE[0]}/..")"
+_root_dir_cnt="$(readlink -m "${BASH_SOURCE[0]}/..")"
 
 # Activate poetry virtual environment
 if [ -z "${VIRTUAL_ENV:-}" ]; then
-  # shellcheck disable=SC2091
-  $(poetry env activate)
+  # shellcheck disable=SC2046,SC1091
+  source $(poetry env info --path)/bin/activate
 fi
 
 # Filter out nix python packages from PYTHONPATH.
@@ -41,9 +41,9 @@ unset BOOTSTRAP_DIR
 mkdir -p "${CARDANO_NODE_SOCKET_PATH%/*}"
 
 # Set temporary directory for this instance
-TMPDIR="$_ROOT_DIR_CNT/tmp"
+TMPDIR="$_root_dir_cnt/tmp"
 if [ "$INSTANCE_NUM" != 0 ]; then
-  TMPDIR="$_ROOT_DIR_CNT/tmp${INSTANCE_NUM}"
+  TMPDIR="$_root_dir_cnt/tmp${INSTANCE_NUM}"
 fi
 mkdir -p "$TMPDIR"
 export TMPDIR
@@ -53,16 +53,16 @@ PATH="$(echo "$PATH" | tr ":" "\n" | grep -v "ghcup" | tr "\n" ":" | sed 's/:*$/
 export PATH
 
 # Prepend instance-specific .bin directory to PATH if it exists and if not already present
-if [ -e "$_ROOT_DIR_CNT/.bin${INSTANCE_NUM}" ] \
-  && [[ ":$PATH:" != *":$_ROOT_DIR_CNT/.bin${INSTANCE_NUM}:"* ]]; then
-  export PATH="$_ROOT_DIR_CNT/.bin${INSTANCE_NUM}:$PATH"
+if [ -e "$_root_dir_cnt/.bin${INSTANCE_NUM}" ] \
+  && [[ ":$PATH:" != *":$_root_dir_cnt/.bin${INSTANCE_NUM}:"* ]]; then
+  export PATH="$_root_dir_cnt/.bin${INSTANCE_NUM}:$PATH"
 fi
 
 # Prepend default .bin directory to PATH for instance 0 if it exists and if not already present
 if [ "$INSTANCE_NUM" = 0 ] \
-  && [ -e "$_ROOT_DIR_CNT/.bin" ] \
-  && [[ ":$PATH:" != *":$_ROOT_DIR_CNT/.bin:"* ]]; then
-  export PATH="$_ROOT_DIR_CNT/.bin:$PATH"
+  && [ -e "$_root_dir_cnt/.bin" ] \
+  && [[ ":$PATH:" != *":$_root_dir_cnt/.bin:"* ]]; then
+  export PATH="$_root_dir_cnt/.bin:$PATH"
 fi
 
 # Set database connection environment variables for db-sync
@@ -73,7 +73,7 @@ if [ -n "${DBSYNC_SCHEMA_DIR:-}" ] && command -v cardano-smash-server >/dev/null
   export SMASH=true
 fi
 
-unset INSTANCE_NUM _ROOT_DIR_CNT
+unset INSTANCE_NUM _root_dir_cnt
 
 # Enable cardano-cli bash completion
 if ! command -v _cardano-cli >/dev/null 2>&1 && command -v cardano-cli >/dev/null 2>&1; then