merge: integrate main restructuring into dev

- Resolve 57 merge conflicts from codebase restructure
- Port dev feature code to new directory structure:
  * Update import paths to use @/ aliases
  * Add backward-compatible API signatures (createInstance, startInstance, deleteInstance)
  * Add missing type exports (ProjectWithRepos, InstanceHealth, Branch, BranchesResponse)
  * Extend Session and GitRepository types for dev features
  * Extend TerminalComponent props for mobile terminal wrapper
  * Add missing icon names (bell, drag, undo)

Quality gates: tsc pass (0 errors), build pass, 127/131 tests pass
(4 pre-existing failures unrelated to merge)

apps/web/src/api/ssh-keys.ts

@@ -0,0 +1,53 @@
+import { apiClient } from "./client";
+
+export interface SSHKey {
+  id: string;
+  name: string;
+  public_key: string;
+  created_at: string;
+}
+
+export interface SSHKeyCreate {
+  name: string;
+}
+
+export async function listSSHKeys(): Promise<SSHKey[]> {
+  const response = await apiClient.get<SSHKey[]>("/ssh-keys");
+  return response.data;
+}
+
+export async function createSSHKey(data: SSHKeyCreate): Promise<SSHKey> {
+  const response = await apiClient.post<SSHKey>("/ssh-keys", data);
+  return response.data;
+}
+
+export async function deleteSSHKey(keyId: string): Promise<void> {
+  await apiClient.delete(`/ssh-keys/${keyId}`);
+}
+
+export interface SignPayloadRequest {
+  payload: string;
+}
+
+export interface SignatureResponse {
+  signature: string;
+}
+
+export interface VerifySignatureRequest {
+  payload: string;
+  signature: string;
+}
+
+export interface VerifySignatureResponse {
+  valid: boolean;
+}
+
+export async function signPayload(keyId: string, data: SignPayloadRequest): Promise<SignatureResponse> {
+  const response = await apiClient.post<SignatureResponse>(`/ssh-keys/${keyId}/sign`, data);
+  return response.data;
+}
+
+export async function verifySignature(keyId: string, data: VerifySignatureRequest): Promise<VerifySignatureResponse> {
+  const response = await apiClient.post<VerifySignatureResponse>(`/ssh-keys/${keyId}/verify`, data);
+  return response.data;
+}