[byRandom]

Proposal #6 of the architecture review: the finder's query and its results had three hand-written front ends (the find example's argv parsing, the app panel, the tests). They now share one model in mc-core.

What changes

• Targets in mc-core (structure::target): each searchable group of structures is a structure set in one dimension, optionally narrowed (fortresses and bastions share a set), and has a stable id. The app's layers take their set, dimension and narrowing from it by id, so the app and the core can no longer disagree. StructureFilter is now { target, radius, min_count, ship_only }.
• A text form for Query (FromStr / Display):
  center=spawn villages:300:2 end_cities+ship:1000 biome=plains,meadow.
  Errors name the problem, for example an unknown structure (listing the valid ids), a bad radius, or +ship on something without ships.
• Match prints as one line: the CLI output and the app's new "copy all results" button use the same line.
• find example: it parses the shared form. That means it can now search Nether and End structures and several biomes. --zero and --biome become center=zero and biome=.
• App finder panel: a query field at the top that you can copy, paste or edit. It stays in sync with the form both ways. Invalid text shows the reason, and goes back to the form's query once the field loses focus. You can still copy it while a search runs.
• Several biomes at the center in the app: the biome list is now multi-select. Saved settings add biomes and keep writing and reading the old single biome.
• Docs: README (query syntax), GLOSSARY (Target, Query), ROADMAP (what 0.8 still needs for stable formats).

Verification

• cargo fmt --all --check && cargo clippy --all-targets -- -D warnings && cargo test pass.
• The find output matches main (sorted) on three searches: sequential with two filters, center=zero with two biomes, and random seeds.
• New tests cover:
  • text-form round trips and defaults;
  • 13 bad queries and their messages;
  • consistency of every target (its set exists in its dimension, only matches a structure);
  • the one-line match format;
  • ship_only on a target without ships;
  • every target having an app layer;
  • old settings with a single biome.
• Mutation testing: 14 mutations of the parser, printer and target code, all caught.
• Checked in the app under Xvfb: typing a query updates the form, an invalid one shows its error, the biome multi-select updates the text, and a search shows results with the copy-all button.

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Generated by Claude Code