schemas: add registry tags schema and audit

[VasilisDragon]

Problem

This PR was originally based on #1080's 1.21.8 four-registry output. The replacement generator work uses full resource locations and can emit any keyed registry, so the schema and repository checks need to cover the final representation.

Fix

• validate full registry, tag and member resource locations while preserving empty tags;
• reject duplicate members and unresolved #tag references;
• add a PC-only audit for canonical ordering, dataPaths targets, orphan files and mapped member references;
• keep additional registry types open while requiring block and item registries in tag-bearing PC data.

Test

• focused positive, negative and corruption controls pass;
• the full tools/js suite passes;
• the schema compiles to the generated Tags type;
• duplicate validation adds about 9 ms across the three tested tag artifacts.

Scope

Schema and audit only. No generated tags data or dataPaths changes are included here.

Refs

• Add TagsDataGenerator to supersede obsolete materials.json with modern tag system for multiple Minecraft versions minecraft-data-generator#56
• Add Minecraft pc 1.21.8 tags #1080
• RFC: Tag Schema #463
• Tag schemas #464
• loader: pass tags through to mcData node-minecraft-data#457

[VasilisDragon]

updated this with the finished schema/audit side of the tags work. rebased on current master and all checks are green

[VasilisDragon]

rebased again after master moved; all checks are green