[SkyBlade1978]

Adds a Mods-list Config screen with help for each setting, improves smoothing
where small plants have already been placed, and keeps exposed grass beneath
Building Pieces steps and corners. Legacy recovery now reports its intentional
registrations once, while retaining the same saved IDs and conversion rules.

Grass Slabs still works on its own. The four permanent block IDs, recipes,
configuration defaults and migration state remain unchanged.

Validation:

• 59 unit tests, fresh/reload runtime suites, Javadocs, Eclipse isolation and
  artifact audits passed.
• A standalone save made with the exact published 1.1.0 jar retained block
  orientations, item counts, custom NBT and schema-1 counters after upgrading
  and reloading. The source fixture hash stayed unchanged.
• The packaged client passed fresh/reload, model, biome-tint, metadata and
  Config-screen checks. Complete runtime logs passed the strict audit.
• Main, sources, Javadocs and checksums matched across repeated builds. Java 8
  bytecode and repository hygiene checks passed.

Updates CI to require the exact 1.1.1.110021 artifacts.

[CLAassistant]

All committers have signed the CLA.