feat(auth): refactor authentication routes and enhance JWT handling

- Removed unused permission and app retrieval logic from the login process.
- Introduced a new endpoint for reissuing access tokens to handle role changes and account switches.
- Updated JWT payload handling to improve clarity and maintainability.
- Enhanced the readJwtPayload function for better decoding of JWT claims.

apps/api/src/lib/issue-access-token.ts

@@ -0,0 +1,52 @@
+import type { FastifyInstance } from 'fastify'
+import {
+  allPermissionKeys,
+  normalizePermissionKeys,
+  tenantsClaimForUser,
+  type LoginResponse,
+} from '@authportal/shared'
+import {
+  getAppSwitcherConfig,
+  getUserApps,
+  getUserPermissions,
+  type UserRow,
+} from '@authportal/db'
+import { toMe } from '../plugins/auth-guards.js'
+
+/** Mint access JWT + Me from current DB state (login / reissue). */
+export function issueAccessToken(
+  app: FastifyInstance,
+  user: UserRow,
+): LoginResponse {
+  const apps = getUserApps(app.db, user.id)
+  let permissions = normalizePermissionKeys(getUserPermissions(app.db, user.id))
+  if (user.isAdmin) {
+    permissions = allPermissionKeys()
+  }
+  const switcher = getAppSwitcherConfig(app.db)
+  const tenants = tenantsClaimForUser(switcher, apps)
+  const me = toMe(user, apps, permissions)
+  const expiresAt = new Date(
+    Date.now() + app.config.jwtTtlHours * 60 * 60 * 1000,
+  )
+  const accessToken = app.jwt.sign(
+    {
+      sub: user.id,
+      email: user.email,
+      name: user.name,
+      apps,
+      permissions,
+      tenants,
+      bgp_tenant_id: tenants.bgp,
+      is_admin: user.isAdmin,
+      iss: app.config.issuer,
+    },
+    { expiresIn: `${app.config.jwtTtlHours}h` },
+  )
+  return {
+    access_token: accessToken,
+    expires_at: expiresAt.toISOString(),
+    token_type: 'Bearer',
+    user: me,
+  }
+}