Antigravity only attaches a workspace rule when its frontmatter declares
a trigger. The antigravity target copied rules verbatim: common rules
have no frontmatter and language rules carry Claude's `paths:` list, so
every ECC rule landed in .agents/rules/ and was never loaded.
Add an antigravity-rule-frontmatter content transform and apply it to
rule pack files on both the manifest and legacy install paths. Rules
without frontmatter become `trigger: always_on`; `paths:` becomes
`trigger: glob` with matching `globs:`. A rule that already declares a
trigger is left alone, and rules/README.md stays inert. Canonical rule
sources are unchanged.
Fixes#3548
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
