feat(governance): add remediation dry run entrypoint

apps/api/src/api/v1/ai_slo.py

@@ -18,8 +18,14 @@ Endpoints:
 from __future__ import annotations
 
 import structlog
-from fastapi import APIRouter, Query
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel, Field
 
+from src.services.adr100_remediation_service import (
+    RemediationMode,
+    RemediationNotFoundError,
+    get_adr100_remediation_service,
+)
 from src.services.adr100_slo_status_service import get_adr100_slo_status_service
 from src.services.ai_slo_calculator import AiSloCalculator
 
@@ -28,6 +34,20 @@ logger = structlog.get_logger(__name__)
 router = APIRouter()
 
 
+class RemediationPreviewRequest(BaseModel):
+    """ADR-100 remediation preview request."""
+
+    work_item_id: str = Field(min_length=1)
+    mode: RemediationMode = "auto"
+
+
+class RemediationDryRunRequest(BaseModel):
+    """ADR-100 remediation dry-run request."""
+
+    work_item_id: str = Field(min_length=1)
+    mode: RemediationMode = "auto"
+
+
 @router.get("/ai/slo")
 async def get_ai_slo(
     force_refresh: bool = Query(False, description="忽略快取，強制重算"),
@@ -59,3 +79,42 @@ async def get_ai_slo(
     data["cache_hit"] = False
     data["adr100"] = await get_adr100_slo_status_service().fetch_report()
     return data
+
+
+@router.get("/ai/slo/remediation/preview")
+async def preview_ai_slo_remediation(
+    work_item_id: str = Query(..., min_length=1),
+    mode: RemediationMode = Query("auto"),
+) -> dict:
+    """Preview the safe remediation plan for one ADR-100 queue item."""
+
+    try:
+        return await get_adr100_remediation_service().preview(work_item_id, mode)
+    except RemediationNotFoundError as exc:
+        raise HTTPException(status_code=404, detail="remediation_work_item_not_found") from exc
+
+
+@router.post("/ai/slo/remediation/preview")
+async def preview_ai_slo_remediation_post(request: RemediationPreviewRequest) -> dict:
+    """POST variant for clients that prefer JSON bodies."""
+
+    try:
+        return await get_adr100_remediation_service().preview(
+            request.work_item_id,
+            request.mode,
+        )
+    except RemediationNotFoundError as exc:
+        raise HTTPException(status_code=404, detail="remediation_work_item_not_found") from exc
+
+
+@router.post("/ai/slo/remediation/dry-run")
+async def dry_run_ai_slo_remediation(request: RemediationDryRunRequest) -> dict:
+    """Run a read-only ADR-100 remediation dry-run."""
+
+    try:
+        return await get_adr100_remediation_service().dry_run(
+            request.work_item_id,
+            request.mode,
+        )
+    except RemediationNotFoundError as exc:
+        raise HTTPException(status_code=404, detail="remediation_work_item_not_found") from exc