fix(queue): scope chamber preheat to mapped trays

[ichwars]

Summary

• derive the chamber preheat target only from the trays named by the selected plate's resolved AMS mapping
• support regular AMS units, AMS-HT global IDs, external spools, fixed-printer jobs, model assignments, and the selected cross-model variant
• retain the conservative all-AMS fallback for missing or unusable mappings, plus existing user overrides and model capability gates
• extract tray resolution from the size-limited scheduler and lower its grandfathered source budget from 3,826 to 3,800 lines

Related Issue

Closes #139

Documentation

• No documentation update required — this corrects internal queue/preheat resolution without changing the user-facing workflow

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• Test addition or update

Upstream comparison

Selectively adapts the chamber-target behavior from maziggy/bambuddy commit 28d386f76. PrintOps' selected-plate mapping, cross-model variant folding, explicit overrides, hardware capability gates, and conservative fallback are preserved. The separate keep-warm feature was intentionally not ported because it remains scoped to #148.

Testing

• Issue regression suite: 15 passed
• Queue/filament regression selection: 381 passed
• Full backend: 8,559 passed, 253 skipped
• Full frontend: 3,041 passed across 267 files; all 11 locales in parity
• Frontend lint, TypeScript typecheck, and isolated production build
• Ruff lint/format, dependency boundaries, source-size budget, compile check, and diff checks

Checklist

• My code follows the project's coding style
• My changes generate no new warnings
• I have tested my changes thoroughly
• No protected PrintOps business-domain behavior was removed

Hardware note

No printer-hardware test was performed. Regular AMS, AMS-HT, external-spool, override, printer-assignment, and cross-model paths are covered by automated regression tests.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-06T18:55:51.091338Z	23b7b04	PR opened

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