fix(tbc): correct rep caps, phase map, attunements

[ivorycrayon]

What

Validates the TBC dungeon-rep guide — previously sourced from a
single spreadsheet — against Wowhead TBC Classic, warcraft.wiki.gg,
Icy Veins, and the 2026 anniversary phase schedule (six research
passes). Fixes every table entry that didn't hold up and adds
verified enrichments.

Corrections:

• Shadow Labyrinth (normal) caps Lower City rep at Revered, not
  Exalted; the factions lead now notes heroics pay through Exalted.
• Sha'tar spillover from Aldor/Scryers turn-ins caps at
  Friendly, not Honored.
• Phase badges remapped to the 2026 anniversary schedule:
  Sunwell / Magisters' Terrace / Shattered Sun p4 (was p5),
  Zul'Aman p3.5 (was p4); phase legend added (p2 live May 14, 2026).
• Heroic Shattered Halls → very hard (community consensus).
• Wazat's cape is green, not blue; Slave Pens kill-order tip explains
  the freed-slave rep cutoff; Underbog tip drops Unidentified Plant
  Parts (they cap at Honored) and adds Coilfang Armaments; Consortium
  card gains its missing Revered/Exalted paths (Zaxxis Insignia,
  Obsidian Warbeads, Ethereum Prison Keys).

Enrichments:

• Keys rules box: heroic keys still need Revered on mains as of
  p2 (the announced Honored change never shipped at the February
  launch — verified against launch-week forum reports), attunements
  are account-wide, alts can use a Communal Heroic Key at Friendly.
• SSC/TK/BT attunement steps name kill requirements (Gruul+Nightbane
  signets, the four trials, Al'ar via Ruse of the Ashtongue); Shadow
  Lab key located at Ikiss's chest; golden rule explains turn-in
  banking; Black Morass noted as paying twice (heroic key + Hyjal
  attune).
• Five new hand-verified Wowhead ids.

Why

The guide was sourced from a single spreadsheet. Cross-checking
found real errors (the Shadow Labyrinth cap, the Sha'tar spillover
ceiling, the phase numbering, which still followed 2021's
five-phase plan) plus several places where the right answer needed
context the spreadsheet couldn't carry — most notably heroic keys,
where the announced Honored change never shipped and Revered still
gates mains as of p2.

Test plan

• python3 tbc/build_tbc_guide.py --check passes (index.html
  regenerated in sync).
• Rendered page eyeballed on live preview: faction badges, phase
  legend, keys rules box, and difficulty tiers all render correctly.

[ivorycrayon]

Verified: all changed facts trace to Wowhead TBC Classic, warcraft.wiki.gg, Icy Veins, and 2026 anniversary phase coverage. The heroic-key requirement and Shadow Labyrinth normal-mode cap were cross-checked against two sources before landing.

Build: index.html regenerated from the generator; CI --check green. Render: new revered/friendly badges, phase legend, keys rules box, and difficulty tiers checked on preview. Leak grep clean.

Merging (squash).