feat(api): add comprehensive repository management API endpoints

- Introduce new repo module with complete repository functionality
- Add endpoints for repository CRUD operations (create, get, update, archive, delete)
- Implement branch management with create, list, delete and protection features
- Add tag management with create, list and delete operations
- Include release management with create, update and delete capabilities
- Support repository forking with sync functionality
- Implement starring and watching mechanisms for repositories
- Add member management with roles and invitations
- Provide deploy key management for CI/CD integration
- Create webhook management for external integrations
- Implement branch protection rules with approval requirements
- Add commit status and comment functionality for code reviews
- Include merge checking logic for pull requests
- Register all new endpoints in OpenAPI documentation
- Configure routes to handle new repository-specific paths

api/repo/accept_invitation.rs

@@ -0,0 +1,61 @@
+use actix_web::{web, HttpResponse};
+use serde::Deserialize;
+use utoipa::ToSchema;
+
+use crate::api::response::{ApiResponse, ApiErrorResponse};
+use crate::error::AppError;
+use crate::models::repos::RepoInvitation;
+use crate::service::AppService;
+use crate::session::Session;
+
+#[derive(Debug, Deserialize, ToSchema)]
+pub struct AcceptInvitationParams {
+    /// Invitation token (received via email)
+    pub token: String,
+}
+
+/// Accept a repository invitation
+///
+/// Accepts a pending repository invitation using the token received via email.
+/// Requires authentication and a verified email address matching the invitation.
+/// 
+/// Effects:
+/// - User is added as a repository member with the invited role
+/// - User is added to the workspace if not already a member
+/// - Invitation is marked as accepted
+/// 
+/// Returns the accepted invitation with full metadata.
+#[utoipa::path(
+    post,
+    path = "/api/v1/repos/invitations/accept",
+    tag = "Repos",
+    operation_id = "repoAcceptInvitation",
+    request_body(
+        content = AcceptInvitationParams,
+        description = "Invitation acceptance parameters",
+        content_type = "application/json"
+    ),
+    responses(
+        (status = 200, description = "Invitation accepted successfully. User is now a member of the repository.", body = ApiResponse<RepoInvitation>),
+        (status = 400, description = "Invalid or expired token, or email doesn't match invitation", body = ApiErrorResponse),
+        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
+        (status = 404, description = "Invitation not found", body = ApiErrorResponse),
+        (status = 409, description = "User is already a member of this repository", body = ApiErrorResponse),
+        (status = 500, description = "Internal server error", body = ApiErrorResponse),
+    ),
+    security(
+        ("session_cookie" = [])
+    )
+)]
+pub async fn accept_invitation(
+    service: web::Data<AppService>,
+    session: Session,
+    params: web::Json<AcceptInvitationParams>,
+) -> Result<HttpResponse, AppError> {
+    let invitation = service
+        .repo
+        .repo_accept_invitation(&session, &params.token)
+        .await?;
+
+    Ok(HttpResponse::Ok().json(ApiResponse::new(invitation)))
+}