Port to Paper 26.2 (2.0.0)

Snapshot of the 26.2 port published on Modrinth as 2.0.0 on 2026-08-06.
Built against paper-api 26.2.build.100-stable on Java 25. The changes had
only lived in the working tree on HPDebian (/root/mc-26.2/repos); this
commit records them as they were shipped. Details are in the 2.0.0 section
of the Modrinth changelog.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/main/resources/plugin.yml

@@ -1,7 +1,7 @@
 name: CommunityMarket
 version: '${project.version}'
 main: pt.henrique.communityMarket.CommunityMarket
-api-version: '1.21'
+api-version: "26.2"
 description: A GUI-only marketplace plugin for fixed-price listings and auctions
 author: Henrique
 website: https://github.com/henriquescrrrr/carrageis-communitymarket