feat: remove legacy OpenCode runtime

Cut product flows over to Coding/Pi and retain only the migration-owned v1 boundary. Promote supported native optional packages because electron-builder omitted pnpm transitive optional closure from the packaged ASAR.

src/lib/coding-projects.ts

@@ -4,6 +4,7 @@ import type {
   CodingProjectConfigSnapshot,
   CodingProjectSummary,
 } from '@/types/coding-project';
+import type { ProjectType } from '../../shared/project-config';
 
 export interface CodingProjectCatalog {
   projects: CodingProjectSummary[];
@@ -14,6 +15,52 @@ export async function listCodingProjects(): Promise<CodingProjectCatalog> {
   return await hostApiFetch<CodingProjectCatalog>('/api/coding/projects');
 }
 
+export async function openCodingProject(projectPath: string): Promise<CodingProjectSummary> {
+  const response = await hostApiFetch<{ project: CodingProjectSummary }>('/api/coding/projects/open', {
+    method: 'POST',
+    body: JSON.stringify({ projectPath }),
+  });
+  return response.project;
+}
+
+export async function createCodingProject(input: {
+  projectPath?: string;
+  parentPath?: string;
+  projectName?: string;
+  projectType?: ProjectType;
+}): Promise<CodingProjectConfigSnapshot> {
+  const response = await hostApiFetch<{ snapshot: CodingProjectConfigSnapshot }>('/api/coding/projects/create', {
+    method: 'POST',
+    body: JSON.stringify(input),
+  });
+  return response.snapshot;
+}
+
+export async function setActiveCodingProject(projectId: string): Promise<CodingProjectSummary> {
+  const response = await hostApiFetch<{ project: CodingProjectSummary }>('/api/coding/projects/active', {
+    method: 'POST',
+    body: JSON.stringify({ projectId }),
+  });
+  return response.project;
+}
+
+export async function removeCodingProject(projectId: string): Promise<void> {
+  await hostApiFetch('/api/coding/projects/remove', {
+    method: 'POST',
+    body: JSON.stringify({ projectId }),
+  });
+}
+
+export async function acknowledgeLegacyCodingConversationNotice(
+  projectId: string,
+): Promise<CodingProjectConfigSnapshot> {
+  const response = await hostApiFetch<{ snapshot: CodingProjectConfigSnapshot }>(
+    '/api/coding/projects/legacy-conversation-notice/acknowledge',
+    { method: 'POST', body: JSON.stringify({ projectId }) },
+  );
+  return response.snapshot;
+}
+
 export async function getCodingProjectConfig(
   projectId: string,
 ): Promise<CodingProjectConfigSnapshot> {