feat: personal access tokens with scoped bearer auth

Add cnp_ personal access tokens so the CLI, MCP server, and external
agents authenticate without a browser session — the agent-first spine
from ROADMAP2 phase A. Modeled on agent_auth_tokens: raw token shown
once, only SHA-256 hash stored.

- user_tokens table (goose migration + sqlc), name/prefix/scope/expiry,
  owner-scoped revoke, last_used_at stamping
- middleware: cnp_ bearer resolution, read scope gates mutations with
  403 SCOPE_INSUFFICIENT, non-admin scopes cap is_admin even for admin
  owners — a token never outranks its scope or its owner
- GET/POST/DELETE /api/v1/user/tokens + OpenAPI + generated types
- Settings UI: create with scope/expiry pickers, one-time token display
  with copy, list with last-used/expiry, confirm-revoke
- docs: OPERATIONS.md section, README feature line

Verified end-to-end against live Postgres: create/list/revoke, read
scope blocks PUT (403), write PAT on admin owner blocked from admin
routes (403), admin scope works, revoked token returns 401.

Authored By: TDvorak <[email protected]>

app/frontend/src/lib/api-client.ts

@@ -993,6 +993,34 @@ export async function revokeAgentToken(id: string): Promise<void> {
   await requestJson(`/agent-tokens/${id}`, { method: 'DELETE' });
 }
 
+export type UserToken = components['schemas']['UserToken'];
+export type UserTokenCreated = components['schemas']['UserTokenCreated'];
+export type UserTokenScope = 'read' | 'write' | 'admin';
+
+export async function createUserToken(input: {
+  name: string;
+  scope?: UserTokenScope;
+  expiresInDays?: number;
+}): Promise<UserTokenCreated> {
+  return requestJson<UserTokenCreated>(`/user/tokens`, {
+    method: 'POST',
+    body: JSON.stringify({
+      name: input.name,
+      scope: input.scope ?? 'write',
+      expires_in_days: input.expiresInDays ?? 0,
+    }),
+  });
+}
+
+export async function listUserTokens(): Promise<UserToken[]> {
+  const payload = await requestJson<{ tokens?: UserToken[] }>(`/user/tokens`);
+  return payload.tokens ?? [];
+}
+
+export async function revokeUserToken(id: string): Promise<void> {
+  await requestJson(`/user/tokens/${id}`, { method: 'DELETE' });
+}
+
 export async function createProject(input: CreateProjectInput): Promise<ProjectEntity> {
   const payload = await requestJson<RawProject | { project?: RawProject }>(`/projects`, {
     method: 'POST',