feat(scripts): add library-policy-nudge hook + smoke tests

Registers .claude/hooks/library-policy-nudge.sh under PreToolUse/Bash
and PostToolUse/Edit|Write|MultiEdit. The hook emits a non-blocking
system-reminder pointing at /evaluate-library before runtime deps are
added via pnpm add or via direct package.json edits, so policy
evaluation happens before the pre-commit gate fires.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/settings.json

@@ -12,6 +12,10 @@
           {
             "type": "command",
             "command": "$CLAUDE_PROJECT_DIR/.claude/hooks/generator-first-nudge.sh"
+          },
+          {
+            "type": "command",
+            "command": "$CLAUDE_PROJECT_DIR/.claude/hooks/library-policy-nudge.sh"
           }
         ]
       }
@@ -23,6 +27,10 @@
           {
             "type": "command",
             "command": "$CLAUDE_PROJECT_DIR/.claude/hooks/post-manifest-edit.sh"
+          },
+          {
+            "type": "command",
+            "command": "$CLAUDE_PROJECT_DIR/.claude/hooks/library-policy-nudge.sh"
           }
         ]
       }