feat(phase109): RuntimeProfile設計で FileBox を条件付き optional に

Phase 109 完全実装完了：
- RuntimeProfile enum (Default, NoFs) で profile 制御
- CoreBoxId.is_required_in(profile) で条件付き required/optional
- initialize_runtime() で env 読み込み責務を一元化（修正1）
- NoFsFileIo スタブで no-fs プロファイルでの FileBox 無効化（修正2）
- Logger/ConsoleService は no-fs でも有効と明示（修正2）
- Profile 拡張予定（TestMock/Sandbox/ReadOnly/Embedded）を予約（修正3）

実装ファイル:
- src/runtime/runtime_profile.rs (新規)
- src/providers/ring1/file/nofs_fileio.rs (新規)
- src/runtime/core_box_ids.rs (修正)
- src/runtime/plugin_host.rs (修正)
- src/runtime/provider_lock.rs (修正)
- docs 更新

テスト: Phase 109 11/11 PASS ✅
ビルド: cargo build --release SUCCESS ✅

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/providers/ring1/file/mod.rs

@@ -1,2 +1,3 @@
 pub mod core_ro;
 pub mod ring0_fs_fileio;
+pub mod nofs_fileio; // Phase 109: NoFs profile stub

src/providers/ring1/file/nofs_fileio.rs

@@ -0,0 +1,98 @@
+//! Phase 109: NoFs profile FileIo stub
+//!
+//! Provides a stub FileIo implementation that returns errors for all operations.
+//! Used when FileBox is disabled in no-fs runtime profile.
+
+use crate::boxes::file::provider::{FileCaps, FileError, FileIo, FileResult};
+
+/// Phase 109: No-filesystem FileIo stub
+///
+/// Returns Unsupported errors for all operations.
+/// Used in NoFs runtime profile where FileBox is disabled.
+///
+/// # Design
+///
+/// - caps(): Returns read=false, write=false
+/// - All operations: Return FileError::Unsupported with clear message
+///
+/// # Logger/ConsoleService availability (Phase 109 Modification 2)
+///
+/// ✅ Still available in NoFs profile:
+/// - Ring0.log (OS abstraction layer - panic/exit final output)
+/// - ConsoleBox (language-level console - stdout/stderr)
+/// - Core required boxes (String/Integer/Bool/Array/Map/Console)
+///
+/// ❌ Disabled in NoFs profile:
+/// - FileBox (filesystem-dependent)
+/// - Optional boxes (Regex/Time/JSON - future: profile-controlled)
+pub struct NoFsFileIo;
+
+impl FileIo for NoFsFileIo {
+    fn caps(&self) -> FileCaps {
+        FileCaps {
+            read: false,
+            write: false,
+        }
+    }
+
+    fn open(&self, _path: &str) -> FileResult<()> {
+        Err(FileError::Unsupported)
+    }
+
+    fn read(&self) -> FileResult<String> {
+        Err(FileError::Unsupported)
+    }
+
+    fn write(&self, _text: &str) -> FileResult<()> {
+        Err(FileError::Unsupported)
+    }
+
+    fn close(&self) -> FileResult<()> {
+        Err(FileError::Unsupported)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_nofs_fileio_caps() {
+        let fileio = NoFsFileIo;
+        let caps = fileio.caps();
+        assert!(!caps.read, "NoFsFileIo should report read=false");
+        assert!(!caps.write, "NoFsFileIo should report write=false");
+    }
+
+    #[test]
+    fn test_nofs_fileio_open_unsupported() {
+        let fileio = NoFsFileIo;
+        let result = fileio.open("/tmp/test.txt");
+        assert!(result.is_err());
+        assert!(result.unwrap_err().to_string().contains("unsupported"));
+    }
+
+    #[test]
+    fn test_nofs_fileio_read_unsupported() {
+        let fileio = NoFsFileIo;
+        let result = fileio.read();
+        assert!(result.is_err());
+        assert!(result.unwrap_err().to_string().contains("unsupported"));
+    }
+
+    #[test]
+    fn test_nofs_fileio_write_unsupported() {
+        let fileio = NoFsFileIo;
+        let result = fileio.write("test");
+        assert!(result.is_err());
+        assert!(result.unwrap_err().to_string().contains("unsupported"));
+    }
+
+    #[test]
+    fn test_nofs_fileio_close_unsupported() {
+        let fileio = NoFsFileIo;
+        let result = fileio.close();
+        assert!(result.is_err());
+        assert!(result.unwrap_err().to_string().contains("unsupported"));
+    }
+}