fix(rustore): отправляем заголовок ruStoreVerCode

[SergeyOstrouhov]

Summary

Restores the RuStore distribution system, which was broken for every package: --distribution_system rustore failed on the very first call with

[CRITICAL] Cannot download application file: Rustore - Failed to get application info. Status: 400, body:

Root cause

Since July 2026 the RuStore backapi.rustore.ru API (behind the kittenx edge proxy) rejects requests that do not carry a client version header, ruStoreVerCode. Without it, both applicationData/overallInfo/{package} and applicationData/download-link return an empty HTTP 400. mdast-cli was not sending this header.

This is not a TLS-fingerprint or User-Agent block (verified: browser TLS impersonation and mobile User-Agents make no difference) and not a per-request anti-bot challenge — a single static header fixes it.

How the server validates the header

Measured against overallInfo:

ruStoreVerCode	Response
header absent	400
non-numeric (abc)	400
< 247 (e.g. 246)	417
>= 247 (247 … 999999999)	200

The server enforces only a lower bound (currently 247); it does not require the value to match the current RuStore client release. Any larger integer is accepted.

Change

• Add the ruStoreVerCode header to the RuStore API requests in get_app_info.
• Default it to a value far above the bound so it never needs bumping as the real client version changes, and allow overriding it via the MDAST_RUSTORE_VER_CODE environment variable in case RuStore ever raises the minimum.

RUSTORE_VER_CODE = os.environ.get('MDAST_RUSTORE_VER_CODE', '2000000000')

Testing

End-to-end download of a real package now succeeds:

mdast_cli --download_only --distribution_system rustore \
          --rustore_package_name ru.adengi --download_path ./downloads

• overallInfo → 200, download-link → 200
• APK downloaded and extracted from the RuStore zip container (valid APK: contains AndroidManifest.xml and classes.dex)
• Verified both the default constant and the MDAST_RUSTORE_VER_CODE env override are applied.