test: courtyard routing through real HTTP

Beads: trasser-multi-obstacle-http. Depends on !67 (merged). Real loopback Spring Boot with isolated H2/storage, four open/sealed courtyard configurations. Multipart upload, 422 below public search minimum, bounded solve, streaming export, typed IDs, report/preview/summary consistency and re-verification of downloaded export. No production changes. Java clean test: 4 passed (2 HTTP tests with 4 scenarios + 2 module tests), no failures/errors/skips. Docs 1133/1133; catalogue225 valid; diff-check passed. Not PostgreSQL/stand qualification, not an independent hidden corpus, not performance evidence. No auto-merge requested. Prepared with Codex.