fix: quote enum values and csv export subtype

app/models/models.py

@@ -6,16 +6,16 @@ import enum
 
 
 class IssueType(str, enum.Enum):
-    MEETING = meeting
-    SUPPORT = support
-    ISSUE = issue
-    MAINTENANCE = maintenance
-    RESEARCH = research
-    REVIEW = review
-    STORY = story
-    TEST = test
-    RESOLUTION = resolution  # 决议案 - 用于 Agent 僵局提交
-    TASK = task  # legacy generic type
+    MEETING = "meeting"
+    SUPPORT = "support"
+    ISSUE = "issue"
+    MAINTENANCE = "maintenance"
+    RESEARCH = "research"
+    REVIEW = "review"
+    STORY = "story"
+    TEST = "test"
+    RESOLUTION = "resolution"  # 决议案 - 用于 Agent 僵局提交
+    TASK = "task"  # legacy generic type
 
 
 class IssueStatus(str, enum.Enum):
@@ -135,7 +135,7 @@ class ProjectMember(Base):
 
 
 class ProjectCodeCounter(Base):
-    __tablename__ = project_code_counters
+    __tablename__ = "project_code_counters"
 
     id = Column(Integer, primary_key=True, index=True)
     prefix = Column(String(16), unique=True, index=True, nullable=False)