feat(integrations): add issue creation and Azure work item support

Add creation flow for integration issues and Azure work items.
Expose Tauri commands to list Azure projects and types.
Also add a command to create integration issues and return the created item.
Preserve the target repository when provider responses omit it and return
the created issue information to the UI.

- Implement Azure-specific URL and payload handling and creation logic
- Add a Svelte CreateIssueDialog and integrate it into IssueCenter
- Add tests to validate creation requests and created-issue parsing

src/lib/git.ts

@@ -718,3 +718,13 @@ export function listAzureIssueStates(baseUrl: string, username: string, token: s
 export function setAzureIssueState(baseUrl: string, username: string, token: string, repository: string, number: number, state: string): Promise<string> {
   return invoke("set_azure_issue_state", { baseUrl, username, token, repository, number, state });
 }
+
+export function listAzureIssueProjects(baseUrl: string, username: string, token: string): Promise<string[]> {
+  return invoke("list_azure_issue_projects", { baseUrl, username, token });
+}
+export function listAzureIssueTypes(baseUrl: string, username: string, token: string, project: string): Promise<string[]> {
+  return invoke("list_azure_issue_types", { baseUrl, username, token, project });
+}
+export function createIntegrationIssue(provider: GitIntegrationProvider, baseUrl: string, username: string, token: string, repository: string, title: string, description: string, workItemType: string): Promise<import("./types").IntegrationIssue> {
+  return invoke("create_integration_issue", { provider, baseUrl, username, token, repository, title, description, workItemType });
+}