fix: prevent repeated task creation after failures

src/agent_gitea/db.py

@@ -207,6 +207,17 @@ class Database:
         ).fetchall()
         return self._task(rows[0]) if rows else None
 
+    def task_for_issue(self, repo_id: int, issue_number: int) -> TaskRecord | None:
+        row = self.conn.execute(
+            """
+            SELECT * FROM tasks
+            WHERE repo_id = ? AND issue_number = ?
+            ORDER BY id DESC LIMIT 1
+            """,
+            (repo_id, issue_number),
+        ).fetchone()
+        return self._task(row) if row else None
+
     def create_task(self, repo_id: int, issue_number: int) -> TaskRecord:
         now = dt_to_db(utcnow())
         self.conn.execute(
@@ -322,13 +333,23 @@ class Database:
         return updated
 
     def retry_task(self, task_id: int) -> TaskRecord:
-        return self.transition(
-            task_id,
-            TaskState.DISCOVERED,
-            message="manual retry",
-            error_message="",
-            clear_lease=True,
+        task = self.get_task(task_id)
+        if task is None:
+            raise ValueError(f"task not found: {task_id}")
+        now = dt_to_db(utcnow())
+        self.conn.execute(
+            """
+            UPDATE tasks
+            SET state = ?, lease_owner = NULL, lease_expires_at = NULL, error_message = NULL, updated_at = ?
+            WHERE id = ?
+            """,
+            (TaskState.DISCOVERED.value, now, task_id),
         )
+        self.conn.commit()
+        self.add_event(task_id, task.state, TaskState.DISCOVERED, "manual retry")
+        updated = self.get_task(task_id)
+        assert updated is not None
+        return updated
 
     def cancel_task(self, task_id: int) -> TaskRecord:
         return self.transition(task_id, TaskState.CANCELLED, message="manual cancellation", clear_lease=True)

src/agent_gitea/scanner.py

@@ -31,7 +31,7 @@ def scan_eligible_issues(
         for issue in db.list_open_issues(repo.id):
             if not is_issue_eligible(issue, labels):
                 continue
-            if db.active_task_for_issue(repo.id, issue.issue_number):
+            if db.task_for_issue(repo.id, issue.issue_number):
                 continue
             task = db.create_task(repo.id, issue.issue_number)
             created.append(task.id)

src/agent_gitea/service.py

@@ -195,8 +195,8 @@ class TaskRunner:
         write_prompt(prompt_path, prompt)
         command = render_command(
             self.config.agents.implementer.command,
-            workspace_path=workspace,
-            prompt_path=prompt_path,
+            workspace_path=workspace.resolve(),
+            prompt_path=prompt_path.resolve(),
             issue_number=issue.issue_number,
             issue_title=issue.title,
             branch_name=branch_name,
@@ -230,8 +230,8 @@ class TaskRunner:
         write_prompt(prompt_path, prompt)
         command = render_command(
             self.config.agents.reviewer.command,
-            workspace_path=workspace,
-            prompt_path=prompt_path,
+            workspace_path=workspace.resolve(),
+            prompt_path=prompt_path.resolve(),
             issue_number=issue.issue_number,
             issue_title=issue.title,
             pr_number=pr_number,