dungeon: update website, prioritize Dungeon Games endpoints, fix description

[Ninjaxan]

Summary

Maintenance update to the dungeon entry — operated by Crypto Dungeon LLC (the chain's team).

dungeon/chain.json:

• website: cryptodungeon.org → dungeongames.io (current canonical site)
• apis.rpc: promote https://rpc.dungeongames.io to first (the team's own infrastructure)
• apis.rest: promote https://api.dungeongames.io to first

dungeon/assetlist.json:

• DGN extended_description: removed inaccurate "permissioned blockchain" and "first permissionless ICS chain" claims. Dungeon Chain is a sovereign Cosmos SDK chain, not an ICS consumer chain. Replaced with a factual sovereign Cosmos SDK / IBC / CosmWasm description.
• DGN socials.website: cryptodungeon.org → dungeongames.io

No third-party RPC/REST entries were removed.

[greptile-apps]

PR author is not in the allowed authors list.

[Ninjaxan]

Hi maintainers — flagging the same greptile non-allowlisted-author status as my previous PRs (#7563 merged, #7652 / #7653 open). Adding context:

• Submitter: @Ninjaxan (Crypto Dungeon LLC). We are the team operating dungeon-1.
• What this PR does: maintenance update to our own chain entry — dungeon/chain.json and dungeon/assetlist.json only.
  1. website updated cryptodungeon.org → dungeongames.io (current canonical site).
  2. Promoted our team-run https://rpc.dungeongames.io and https://api.dungeongames.io to first in apis.rpc / apis.rest. No third-party endpoints removed.
  3. Rewrote DGN extended_description to drop inaccurate "permissioned blockchain" and "first permissionless ICS chain" claims — dungeon-1 is a sovereign Cosmos SDK chain, not an ICS consumer. Replaced with a factual sovereign-chain / IBC / CosmWasm description.
  4. DGN socials.website updated to the canonical site.
• Companion PR: mirrored at dungeon: update website to dungeongames.io and use Dungeon Games rpc/rest chainapsis/keplr-chain-registry#1463.

Since we operate the chain itself, this is the team's authoritative update — same author as the merged Dungeon Games endpoints PR (#7563). Thanks for taking a look.