fix(bid-ffi): Fix HostVtable lifetime issue causing segfault

🚨 Critical memory safety fix:
- HostVtable was created on stack and destroyed after init
- Plugin stored reference to destroyed memory → NULL pointer access
- Changed to static LazyLock storage for lifetime safety

✅ Results:
- Segfault completely eliminated
- Plugin logging now works properly
- Type info system confirmed working
- Full E2E FileBox plugin operation successful

🔧 Generated with [Claude Code](https://claude.ai/code)

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

tools/plugin-tester/src/main.rs

@@ -72,6 +72,14 @@ enum Commands {
         #[arg(short, long, default_value = "Hello TLV Debug!")]
         message: String,
     },
+    /// Validate plugin type information against nyash.toml
+    Typecheck {
+        /// Path to plugin .so file
+        plugin: PathBuf,
+        /// Path to nyash.toml configuration file
+        #[arg(short, long, default_value = "../../nyash.toml")]
+        config: PathBuf,
+    },
 }
 
 // ============ Host Functions (テスト用実装) ============