Improve pairing planning and statistics visibility

backend/app/models/schemas.py

@@ -284,7 +284,7 @@ class PairingRequest(BaseModel):
     slave_date_to: Optional[str] = Field(default=None, pattern=r'^\d{8}$|^$')
 
     # === 配对策略（新增） ===
-    strategy: str = Field(default="dinsar_production", pattern=r'^dinsar_production$')
+    strategy: str = Field(default="dinsar_production", pattern=r'^(dinsar_production|dinsar_province_coverage)$')
     num_connections: int = Field(default=1, ge=1, le=10)
     reference_image_id: Optional[int] = None
 
@@ -307,7 +307,8 @@ class PairingRequest(BaseModel):
             normalized['overlap_threshold'] = normalized['pair_footprint_overlap_min_ratio']
         if normalized.get('footprint_center_distance_max_meters') not in (None, ''):
             normalized['spatial_baseline_max_meters'] = normalized['footprint_center_distance_max_meters']
-        normalized['strategy'] = 'dinsar_production'
+        if normalized.get('strategy') not in {'dinsar_production', 'dinsar_province_coverage'}:
+            normalized['strategy'] = 'dinsar_production'
         return normalized
 
     @field_validator(
@@ -390,6 +391,11 @@ class RadarPair(BaseModel):
     selection_strategy: Optional[str] = None
     selection_score: Optional[float] = None
     selection_reason: Optional[str] = None
+    coverage_rank: Optional[int] = None
+    aoi_new_area_ratio: Optional[float] = None
+    aoi_pair_area_ratio: Optional[float] = None
+    aoi_coverage_ratio_after: Optional[float] = None
+    effective_coverage_geojson: Optional[Dict[str, Any]] = None
     time_baseline_days: int
     spatial_baseline_meters: float
     scene_center_distance_meters: Optional[float] = None
@@ -416,6 +422,7 @@ class PairingResponse(BaseModel):
     network_run_id: Optional[str] = None
     candidate_count: int = 0
     selected_edge_count: int = 0
+    coverage: Optional[Dict[str, Any]] = None
 
 
 class PsRequest(BaseModel):