feat: M0 monorepo skeleton with services, clients, deploy and CI

- api/openapi.yaml: contract with /healthz, /readyz, /api/v1/server-info
- services/api (Go): api with oapi-codegen strict server, goose migrations,
  readiness checks for Postgres/Redis; storage-agent stub with internal token
- services/recommender (Python, uv): FastAPI health/readiness/internal status,
  `pipu-rec serve` and `pipu-rec analyze` entrypoints
- packages: generated api-client, core (server URL + server check),
  i18n (ru/en + dictionary check), design-tokens (CSS vars + TS from tokens.json)
- apps/web: Vite + React shell showing server status, language switch
- apps/mobile: Expo (SDK 53) Android app with server connect screen
- deploy: Dockerfiles, compose (prod + dev), nginx template, install/update scripts
- .gitea/workflows: ci.yml and tag-based release.yml (images, signed APK, release)
- scripts/version.mjs: version and Android versionCode from git tag
- tests/fixtures/music/generate.sh: synthetic test library via ffmpeg
- docs: versionCode formula, OpenAPI 3.0.3, dev instructions in README

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

services/api/internal/platform/config/config_test.go

@@ -0,0 +1,26 @@
+package config
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLoadAPIDefaults(t *testing.T) {
+	t.Setenv("DATABASE_URL", "postgres://localhost/pipu")
+	t.Setenv("REDIS_URL", "redis://localhost:6379/0")
+
+	cfg, err := Load[API]()
+	require.NoError(t, err)
+	assert.Equal(t, ":8080", cfg.HTTPAddr)
+	assert.Equal(t, []string{"ru", "en"}, cfg.SupportedLocales)
+	assert.True(t, cfg.MigrateOnStart)
+}
+
+func TestLoadAPIRequiresDatabase(t *testing.T) {
+	t.Setenv("REDIS_URL", "redis://localhost:6379/0")
+
+	_, err := Load[API]()
+	assert.ErrorContains(t, err, "DATABASE_URL")
+}