Loadout v0.6.0

• Remove Loadout's FPS cap: Steam's QAM frame limit works for every
  game. Profiles show the target they're made for ("Made for 40 FPS at
  1280x720"). A cap block from 0.5.0 or older is removed on the next
  apply. Launch options stay for per-game env and args.
• Remove the Uncapped profile (without the cap it was Performance again).
  Profiles: Quality, Balanced, Performance, plus Default.
• Profile list shows only the profiles the device's (or borrowed) block
  has; applying one it doesn't have is refused (games.profile_spec).
• ELDEN RING: Quality only (40 FPS costs too much image quality).
• Baldur's Gate 3 (native Linux): Quality only, FSR 2.2 Quality, mostly
  Low with Medium textures, VSync and the game's frame cap off.
• lsxcfg: Larian .lsx read/set by MapKey, byte-preserving. Absent key =
  the game's default: null removes the entry, a missing int32 is added,
  and Default undoes both.
• {xdg_data} path root (~/.local/share, Steam's folder refused) for
  native games' settings.
• Device detected at load, generic if unknown: no Setup screen. Reset
  Loadout clears settings and stays on the main screen.
• Recommended resolution per profile (shown, never written).
• Confirm modal leads with a plain summary; full diff under Show details.
• Games without an entry are no longer listed, except while a profile
  from an older version is applied ("(no settings)").
• Docs: README, GAMES, CONTRIBUTING, AGENTS.

Full Changelog: v0.5.0...v0.6.0