Add rtk init --agent kilocode and rtk init --agent antigravity commands.
Kilo Code: installs .kilocode/rules/rtk-rules.md (project-scoped)
Google Antigravity: installs .agents/rules/antigravity-rtk-rules.md (project-scoped)
Both follow the same prompt-level guidance pattern as Cline and Windsurf,
using rules files that instruct the agent to prefix shell commands with rtk.
Creates docs/README.md (interface contract defining 3-tab structure,
required frontmatter, and conventions) and 4 stub pages with valid
frontmatter for docs/guide/, docs/reference/, and docs/architecture/.
These are the prerequisites for the prepare-docs.mjs pipeline (Plan B)
and for Adrien's Phase 1 content work.
No existing files modified.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Florian BRUNIAUX <florian@bruniaux.com>