v4.0.13

v4.0.13

Release highlights:

Security fixes:

• L3 updater downgrade guard — blocks the v4.0.12 downgrade-hijack
  bug that could silently install older versions
• L2 installer self-check — refuses to run if a newer installer is
  already registered in Add/Remove Programs

Functional fixes:

• F4 Olostep Browser install flow — correct Squirrel detection path,
  no-flag invocation, stray-process taskkill sweep, and bounded-poll
  verification that correctly handles Squirrel's async teardown
• N1 'Check for Updates' dialog now distinguishes up-to-date from
  update-launched and shows the installed version
• N2 'Fry Networks' (with space) user-visible branding + legacy .lnk
  migration for shortcuts from prior versions

Build infrastructure:

• SHA256 checksums emitted for all release artifacts (MSI + EXE +
  updater)
• MSI filename aligned with release naming convention
• Updater registry discovery now queries both 64-bit and 32-bit
  (WOW6432Node) views for compatibility with legacy installs

13-commit series on top of v4.0.12 (e9f2b9e..45c53fb).