Tracking: Roll out nixica 0.2.0 to all consumers

Overview

nixica 0.2.0 has been tagged with the flake check fix (MR !4 (merged), !5 (merged)). All consumer projects need to be updated from 0.1.0 → 0.2.0.

Tier 1 — Direct consumers (bump nixica input to refs/tags/0.2.0)

• nix/gitlab-ci (#78) — needs new release tag after bump
• nix/horizon-flake-parts (#66) — needs new release tag after bump
• nix/ghc-common-hadrian (#76)
• nix/horizon-supported-systems (#67)
• nix/haskell-make-package-set (#77)
• nix/werrorwolf (#49)
• agent-resources/agent-roster (#98)

Tier 2 — Followers via horizon-flake-parts (blocked on Tier 1)

These follow horizon-flake-parts/nixica, so they need the new horizon-flake-parts tag first.

• package-sets/horizon-build-packages (#41)
• ghc/horizon-ghc (#40)
• package-sets/horizon-core (#12)
• haskell/horizon-gen-nix (#5)
• haskell/horizon-spec (#4)

Key change in 0.2.0

• Fixes nix flake check for consumer projects by removing unconditional flake-parts.flakeModules.flakeModules import from modular.nix
• Re-exports flakeModules via nixica.flakeModules.flakeModules for module-provider projects
• Adds it-passes-flake-check regression test

/cc @smartypants @nastypants