1.0.0-rc.6

1.0.0-rc.6 — the release candidate the 1.0 gate needed

Cut from 265def6. The tree at this commit reads 0.25.0 / 7.25.0: a pre-release
version is never committed (scripts/check-no-prerelease-versions.sh), so this
annotation is the only record of what shipped.

npm 1.0.0-rc.6 (14 packages, dist-tag next)
PyPI 1.0.0rc6
NuGet 1.0.0-rc.6 (4 packages)
Maven Central 8.0.0-rc.6 (18 modules)

metamodelVersion 1.0 — unchanged from rc.5; no registered vocabulary moved.

Why this RC exists. Estate 7 hit the exact hazard F52 exists for — apiPrefix
"/api/admin" with no baseUrl passed anywhere, so every generated admin hook would
have 404'd against a tree that compiles, builds and passes every gate — and rc.5
carried no advisory for it. The base-URL scanner is on main and therefore in this
candidate; promoting rc.5 would have shipped 1.0's evidence from a build that
could not warn about it.

Also new since rc.5 (39 commits):

• gen --baseline=adopt (TS/Python/C#) — record the files you HAVE as the merge
  base and write nothing. The no-manifest refusal's leading remedy ("commit
  .hashes.json") could not be performed by the population it named.
• BREAKING: a refused file now FAILS gen on Python and C# (exit 1), as it
  always has on TypeScript. Both warned and exited 0, so a gen wired into CI
  as a drift gate was green while codegen refused to write.
• the @forge* vocabulary leaves the default provider composition; meta docs
  defaults outDir to ./docs/generated; the sdk's .meta path helpers and forge
  record store are removed; Python's version coordinates carry the major.