feat(api): ActionType.SSH_COMMAND + auto_repair_service SSH分支 (Task 12)

- playbook.py: 新增 SSH_COMMAND ActionType
- auto_repair_service._execute_step: SSH_COMMAND 分支，格式 layer/component

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

apps/api/src/models/playbook.py

@@ -47,6 +47,7 @@ class ActionType(str, Enum):
     KUBECTL = "kubectl"  # Kubernetes 命令
     SCRIPT = "script"  # 腳本執行
     MANUAL = "manual"  # 需人工操作
+    SSH_COMMAND = "ssh_command"  # 2026-04-05 Claude Code: 主機層 SSH 修復 (Sprint 3)
 
 
 class RiskLevel(str, Enum):

apps/api/src/services/auto_repair_service.py

@@ -497,6 +497,20 @@ class AutoRepairService:
                 logger.warning("action_executor_not_available")
                 return "SKIPPED (executor not available)"
 
+        # 2026-04-05 Claude Code: SSH_COMMAND — 主機層修復 (Sprint 3 Host Auto-Repair)
+        if step.action_type == ActionType.SSH_COMMAND:
+            from src.services.host_repair_agent import HostRepairAgent
+            agent = HostRepairAgent()
+            # step.command 格式: "<layer>/<component>" 例如 "docker-110/sentry"
+            try:
+                layer, component = step.command.split("/", 1)
+            except ValueError:
+                return f"FAILED: invalid ssh_command format '{step.command}' (expected layer/component)"
+            result = await agent.repair(layer=layer, component=component)
+            if result.success:
+                return f"SUCCESS: {result.output}"
+            return f"FAILED: {result.error}"
+
         return "UNKNOWN_ACTION_TYPE"
 
     # === ADR-037: Tier-based Repair (2026-03-29) ===