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>

scripts/version.test.mjs

@@ -0,0 +1,25 @@
+import assert from 'node:assert/strict';
+import { test } from 'node:test';
+
+import { parseVersion } from './version.mjs';
+
+test('release tag', () => {
+  assert.deepEqual(parseVersion('v0.1.0'), { version: '0.1.0', versionCode: 10_099, prerelease: false });
+  assert.deepEqual(parseVersion('v1.2.3'), { version: '1.2.3', versionCode: 1_020_399, prerelease: false });
+});
+
+test('release candidate', () => {
+  assert.deepEqual(parseVersion('v1.2.0-rc.2'), { version: '1.2.0-rc.2', versionCode: 1_020_002, prerelease: true });
+});
+
+test('version codes grow monotonically', () => {
+  const order = ['v0.9.9', 'v1.0.0-rc.1', 'v1.0.0-rc.2', 'v1.0.0', 'v1.0.1', 'v1.1.0', 'v2.0.0'];
+  const codes = order.map((t) => parseVersion(t).versionCode);
+  assert.deepEqual([...codes].sort((a, b) => a - b), codes);
+});
+
+test('rejects malformed tags', () => {
+  for (const tag of ['1.2', 'v1.2.3-beta', 'v1.100.0', 'v1.2.3-rc.0', 'main']) {
+    assert.throws(() => parseVersion(tag), undefined, tag);
+  }
+});