feat(api): add pull request and wiki API endpoints with OpenAPI generator

- Add gen_openapi binary for generating OpenAPI specification
- Implement comprehensive pull request API endpoints including core operations
- Add pull request reviews, check runs, labels, assignees, and events APIs
- Include pull request status and merge strategy management endpoints
- Add wiki page CRUD operations with revision history and comparison
- Update OpenAPI documentation with Pull Requests and Wiki tags
- Modify workspace find function visibility for external access
- Integrate new API modules into main OpenAPI router configuration

api/pr/reopen.rs

@@ -0,0 +1,55 @@
+use actix_web::{web, HttpResponse};
+use serde::Deserialize;
+use utoipa::IntoParams;
+
+use crate::api::response::{ApiResponse, ApiErrorResponse};
+use crate::error::AppError;
+use crate::models::prs::PullRequest;
+use crate::service::AppService;
+use crate::session::Session;
+
+#[derive(Debug, Deserialize, IntoParams)]
+pub struct PathParams {
+    /// Workspace name (unique identifier)
+    pub workspace_name: String,
+    /// Repository name (unique within the workspace)
+    pub repo_name: String,
+    /// PR number (unique within the repository)
+    pub number: i64,
+}
+
+/// Reopen a pull request
+///
+/// Reopens a closed (but not merged) PR.
+/// Requires write access to the PR.
+///
+/// Returns the reopened PR.
+#[utoipa::path(
+    post,
+    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reopen",
+    tag = "Pull Requests",
+    operation_id = "prReopen",
+    params(PathParams),
+    responses(
+        (status = 200, description = "PR reopened successfully.", body = ApiResponse<PullRequest>),
+        (status = 400, description = "PR is not closed or already merged", body = ApiErrorResponse),
+        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
+        (status = 403, description = "Insufficient permissions", body = ApiErrorResponse),
+        (status = 404, description = "PR not found", body = ApiErrorResponse),
+        (status = 500, description = "Internal server error", body = ApiErrorResponse),
+    ),
+    security(
+        ("session_cookie" = [])
+    )
+)]
+pub async fn reopen(
+    service: web::Data<AppService>,
+    session: Session,
+    path: web::Path<PathParams>,
+) -> Result<HttpResponse, AppError> {
+    let pr = service
+        .pr
+        .pr_reopen(&session, &path.workspace_name, &path.repo_name, path.number)
+        .await?;
+    Ok(HttpResponse::Ok().json(ApiResponse::new(pr)))
+}