LOF 1.6.3 - Safer alt upgrades & clearer popups

Fixes

• ALT UPGRADE on gear LOF had not loaded yet. LOF only knows your alts' gear as a link. When the game had not loaded that item yet, the comparison ran against an empty item: a grey item could become an "upgrade" over better green gear ("Compared with: Unknown"). This existed since 1.3.0. Now an item LOF cannot read is never an upgrade, the bag item stays protected until the data is there, and your alts' worn gear is loaded right after login. This probably also explains an alt upgrade that sometimes "disappeared" from the loot.

Popups

• NOT WORTH A SWAP has a red background next to its red border, so it no longer looks like a plain swap. NOTHING TO SWAP and LOOT LEFT BEHIND share this style.
• The swap note reads neutral: "The only item in your bags worth less than this loot." / "The last item in your bags worth less than this loot." (no more "Need more room? Use Room in the Swap section first.").

Info tab and Guide

• The Info tab is regrouped: About, Guide (Open Guide button) and Support with the website, Discord, mail and version info, each ready to copy.
• Guide > How to use starts with a box linking to the website.

Under the hood

• LOF only recomputes upgrade answers when an item it asked for actually arrives; an item that does not exist is struck off and stays protected.

Known, postponed

• Percentages can look huge when your current item scores almost nothing for your spec (for example over +1300% for a caster with a plain melee staff). The number is correct; a clearer way to show it comes later.
• In the first seconds after login a real ALT UPGRADE can still be missing while your alts' gear loads (fail safe: nothing is deleted).
• A clean-up round for duplicate code follows after the release.