Web: Spanish-first staff UI — login + unified customer browser

First real frontend feature against the live Customer module API.

- login/ — session login form posting to /auth/login with credentials
  included; the session cookie is what every subsequent request rides on.
- clientes/ — customer list with search and the cross-line stats header
  (customers, utilities/insurance split, both-lines count).
- clientes/[id]/ — unified detail view: identity, properties + services,
  policies, and transaction history for one customer, which is the whole
  point of the migration (one record spanning both business lines).
- components/AppShell.tsx, lib/{api,labels,types}.ts — shared fetch wrapper
  (always credentials: "include"), Spanish label maps for the enum values
  the API returns, and the API response types.
- globals.css + layout.tsx — Spanish-first document (lang="es"), the type
  scale, and the design tokens the pages share. Fonts load via <link> so an
  offline build still renders on the system fallback stacks.
- page.tsx now redirects / to /clientes.

Also fixes pnpm-workspace.yaml: the allowBuilds map held pnpm's literal
placeholder text ("set this to true or false"), which made every install
fail with ERR_PNPM_IGNORED_BUILDS. Since pnpm 11 auto-installs before
running a script, that broke `pnpm start:dev` outright. Set the values to
true and dropped the superseded onlyBuiltDependencies list.

Verified: both apps build clean, and login -> /auth/me -> /customers/stats
round-trips against the dev database (1682 customers, 526 on both lines).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -12,4 +12,6 @@ __pycache__/
 *.pyc
 packages/database/generated/
 .DS_Store
+.idea/
+*.tsbuildinfo