fix(dev): normalize npm cache paths and add maven function guard

- Normalize npm cache paths with pwd -P to handle symlinks and
  trailing slashes, preventing duplicate scans of same directory
- Add declare -f check before calling clean_maven_repository for
  robustness when dynamic source fails
- Add test for trailing slash handling

Addresses: dev.sh (line 27, 48, 602)

lib/clean/dev.sh

@@ -44,8 +44,18 @@ clean_dev_npm() {
         safe_clean "$npm_default_cache/${npm_residual_dirs[$i]}"/* "${npm_descriptions[$i]}"
     done
 
+    # Normalize paths for comparison (remove trailing slash + resolve symlinked dirs)
+    local npm_cache_path_normalized="${npm_cache_path%/}"
+    local npm_default_cache_normalized="${npm_default_cache%/}"
+    if [[ -d "$npm_cache_path_normalized" ]]; then
+        npm_cache_path_normalized=$(cd "$npm_cache_path_normalized" 2> /dev/null && pwd -P) || npm_cache_path_normalized="${npm_cache_path%/}"
+    fi
+    if [[ -d "$npm_default_cache_normalized" ]]; then
+        npm_default_cache_normalized=$(cd "$npm_default_cache_normalized" 2> /dev/null && pwd -P) || npm_default_cache_normalized="${npm_default_cache%/}"
+    fi
+
     # Clean custom npm cache path (if different from default)
-    if [[ "$npm_cache_path" != "$npm_default_cache" ]]; then
+    if [[ "$npm_cache_path_normalized" != "$npm_default_cache_normalized" ]]; then
         for i in "${!npm_residual_dirs[@]}"; do
             safe_clean "$npm_cache_path/${npm_residual_dirs[$i]}"/* "${npm_descriptions[$i]} (custom path)"
         done
@@ -600,7 +610,9 @@ clean_dev_jvm() {
     # Source Maven cleanup module (requires bash for BASH_SOURCE)
     # shellcheck disable=SC1091
     source "$(dirname "${BASH_SOURCE[0]}")/maven.sh" 2> /dev/null || true
-    clean_maven_repository
+    if declare -f clean_maven_repository > /dev/null 2>&1; then
+        clean_maven_repository
+    fi
     safe_clean ~/.sbt/* "SBT cache"
     safe_clean ~/.ivy2/cache/* "Ivy cache"
     safe_clean ~/.gradle/caches/* "Gradle cache"

tests/clean_dev_caches.bats

@@ -133,6 +133,32 @@ EOF
     [[ "$output" != *"(custom path)"* ]]
 }
 
+@test "clean_dev_npm treats default cache path with trailing slash as same path" {
+    run env HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" bash --noprofile --norc <<'EOF'
+set -euo pipefail
+source "$PROJECT_ROOT/lib/core/common.sh"
+source "$PROJECT_ROOT/lib/clean/dev.sh"
+start_section_spinner() { :; }
+stop_section_spinner() { :; }
+clean_tool_cache() { :; }
+safe_clean() { echo "$2|$1"; }
+note_activity() { :; }
+run_with_timeout() { shift; "$@"; }
+npm() {
+    if [[ "$1" == "config" && "$2" == "get" && "$3" == "cache" ]]; then
+        echo "$HOME/.npm/"
+        return 0
+    fi
+    return 0
+}
+clean_dev_npm
+EOF
+
+    [ "$status" -eq 0 ]
+    [[ "$output" == *"npm cache directory|$HOME/.npm/_cacache/*"* ]]
+    [[ "$output" != *"(custom path)"* ]]
+}
+
 @test "clean_dev_docker skips when daemon not running" {
     run env HOME="$HOME" PROJECT_ROOT="$PROJECT_ROOT" MO_DEBUG=1 DRY_RUN=false bash --noprofile --norc <<'EOF'
 set -euo pipefail