feat(runtime): Phase 103 CoreServices Optional化 - Memory Constraints対応

- Add CoreServicesConfig struct (from_env, minimal, all_enabled)
- Implement with_core_from_registry_optional() for selective initialization
- Update CoreBoxesImpl fields to Option<Arc<dyn XyzService>>
- Maintain backward compatibility (with_core_from_registry calls all_enabled)
- Add NYASH_CORE_DISABLE_* environment variable support
- ConsoleBox remains mandatory (Graceful Degradation principle)
- Add unit tests for optional initialization
- Update console_println! macro to handle Option type
- Fix direct console.println() calls in vm.rs and selfhost.rs
- Create core_optional_design.md documentation

Note: Phase 104 will extend ConsoleService to be optional as well with
graceful fallback in console_println! macro.

Files modified:
- src/runtime/plugin_host.rs (CoreServicesConfig, with_core_from_registry_optional, tests)
- src/runtime/core_services.rs (CoreBoxesImpl fields → Option type)
- src/runtime/mod.rs (console_println! macro updated)
- src/runner/modes/vm.rs (handle Option console)
- src/runner/selfhost.rs (handle Option console)
- docs/development/current/main/core_optional_design.md (new)
- docs/development/current/main/ring0-inventory.md (Phase 103 entry)

Test results:
- Build: ✅ Success (0 errors, 7 warnings)
- Unit tests: ✅ 3/3 passed (optional_core_tests)
- Runtime tests: ✅ 63/63 passed
- Smoke tests: ✅ 30/31 passed (1 pre-existing timeout)

src/mir/builder/observe/resolve.rs

@@ -1,4 +1,5 @@
 use super::super::MirBuilder;
+use crate::runtime::get_global_ring0;
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::OnceLock;
 
@@ -62,9 +63,9 @@ fn record_kpi(meta: &serde_json::Value) {
         } else {
             0.0
         };
-        eprintln!(
+        get_global_ring0().log.info(&format!(
             "[NYASH-KPI] resolve.choose Known={} Total={} ({:.1}%)",
             known, total, rate
-        );
+        ));
     }
 }

src/mir/builder/observe/types.rs

@@ -5,6 +5,7 @@
 //! TypeRegistry の移行なしに観測ラインを確保する小粒ガードだよ。
 
 use crate::mir::{MirType, ValueId};
+use crate::runtime::get_global_ring0;
 use std::sync::OnceLock;
 
 fn enabled() -> bool {
@@ -15,20 +16,27 @@ fn enabled() -> bool {
 /// Trace when a newbox/class origin is registered.
 pub fn origin(event: &str, vid: ValueId, class: &str) {
     if enabled() {
-        eprintln!("[type-trace] origin:{} %{} ← {}", event, vid.0, class);
+        get_global_ring0()
+            .log
+            .debug(&format!("[type-trace] origin:{} %{} ← {}", event, vid.0, class));
     }
 }
 
 /// Trace when a concrete MirType is recorded.
 pub fn ty(event: &str, vid: ValueId, ty: &MirType) {
     if enabled() {
-        eprintln!("[type-trace] type:{} %{} ← {:?}", event, vid.0, ty);
+        get_global_ring0()
+            .log
+            .debug(&format!("[type-trace] type:{} %{} ← {:?}", event, vid.0, ty));
     }
 }
 
 /// Trace propagation between ValueIds.
 pub fn propagate(event: &str, src: ValueId, dst: ValueId) {
     if enabled() {
-        eprintln!("[type-trace] propagate:{} %{} → %{}", event, src.0, dst.0);
+        get_global_ring0().log.debug(&format!(
+            "[type-trace] propagate:{} %{} → %{}",
+            event, src.0, dst.0
+        ));
     }
 }

src/mir/builder/type_registry.rs

@@ -6,6 +6,7 @@
 //! 🔄 戻せる: NYASH_TYPE_REGISTRY_TRACE=1 で詳細ログ
 
 use crate::mir::{MirType, ValueId};
+use crate::runtime::get_global_ring0;
 use std::collections::HashMap;
 
 /// 型情報追跡エントリ（デバッグ用）
@@ -62,7 +63,9 @@ impl TypeRegistry {
                 timestamp: self.trace_log.len(),
             };
             self.trace_log.push(entry.clone());
-            eprintln!("[type-registry] {} {:?}", entry.source, vid);
+            get_global_ring0()
+                .log
+                .debug(&format!("[type-registry] {} {:?}", entry.source, vid));
         }
     }
 
@@ -78,8 +81,10 @@ impl TypeRegistry {
                     source: format!("param:{}:{:?}", param_name, ty),
                     timestamp: self.trace_log.len(),
                 };
-                self.trace_log.push(entry.clone());
-                eprintln!("[type-registry] {} {:?}", entry.source, vid);
+            self.trace_log.push(entry.clone());
+                get_global_ring0()
+                    .log
+                    .debug(&format!("[type-registry] {} {:?}", entry.source, vid));
             }
         } else if self.trace_enabled {
             let entry = TraceEntry {
@@ -88,7 +93,9 @@ impl TypeRegistry {
                 timestamp: self.trace_log.len(),
             };
             self.trace_log.push(entry.clone());
-            eprintln!("[type-registry] {} {:?}", entry.source, vid);
+            get_global_ring0()
+                .log
+                .debug(&format!("[type-registry] {} {:?}", entry.source, vid));
         }
     }
 
@@ -103,7 +110,9 @@ impl TypeRegistry {
                 timestamp: self.trace_log.len(),
             };
             self.trace_log.push(entry.clone());
-            eprintln!("[type-registry] {} {:?}", entry.source, vid);
+            get_global_ring0()
+                .log
+                .debug(&format!("[type-registry] {} {:?}", entry.source, vid));
         }
     }
 
@@ -119,7 +128,9 @@ impl TypeRegistry {
                 timestamp: self.trace_log.len(),
             };
             self.trace_log.push(entry.clone());
-            eprintln!("[type-registry] {} {:?}", entry.source, vid);
+            get_global_ring0()
+                .log
+                .debug(&format!("[type-registry] {} {:?}", entry.source, vid));
         }
     }
 
@@ -142,7 +153,9 @@ impl TypeRegistry {
                     timestamp: self.trace_log.len(),
                 };
                 self.trace_log.push(entry.clone());
-                eprintln!("[type-registry] {} {:?}", entry.source, dst);
+                get_global_ring0()
+                    .log
+                    .debug(&format!("[type-registry] {} {:?}", entry.source, dst));
             }
         }
 
@@ -156,7 +169,9 @@ impl TypeRegistry {
                     timestamp: self.trace_log.len(),
                 };
                 self.trace_log.push(entry.clone());
-                eprintln!("[type-registry] {} {:?}", entry.source, dst);
+                get_global_ring0()
+                    .log
+                    .debug(&format!("[type-registry] {} {:?}", entry.source, dst));
             }
         }
     }
@@ -192,17 +207,19 @@ impl TypeRegistry {
         // フォールバック: コンテキスト名（警告付き）
         if let Some(ctx) = fallback_context {
             if self.trace_enabled {
-                eprintln!(
+                get_global_ring0().log.warn(&format!(
                     "[type-registry] WARNING: fallback to context '{}' for %{}",
                     ctx, vid.0
-                );
+                ));
             }
             return ctx.to_string();
         }
 
         // 最終フォールバック: UnknownBox
         if self.trace_enabled {
-            eprintln!("[type-registry] WARNING: UnknownBox for %{}", vid.0);
+            get_global_ring0()
+                .log
+                .warn(&format!("[type-registry] WARNING: UnknownBox for %{}", vid.0));
         }
         "UnknownBox".to_string()
     }