[Code Quality] Add antigravity engine to docs and fix dispatch_repository deprecated alias in frontmatter-full.md

[github-actions]

Description

Two documentation consistency issues identified across schema checks on 2026-07-16 and 2026-07-17:

1. Missing antigravity engine in docs: The runtime supports an antigravity engine (present in pkg/workflow/engine_definition.go and used by .github/workflows/smoke-antigravity.md), but docs/src/content/docs/reference/engines.md only lists Copilot, Claude, Codex, Gemini, OpenCode, and Pi.

2. Deprecated dispatch_repository alias still shown in docs: The parser warns users to rename dispatch_repository to dispatch-repository, and the schema marks it as deprecated. However docs/src/content/docs/reference/frontmatter-full.md still shows a standalone example block for dispatch_repository: {}, which contradicts the parser's deprecation warning.

Suggested Changes

• Add antigravity to the engine reference table in docs/src/content/docs/reference/engines.md
• Remove or annotate the dispatch_repository example in docs/src/content/docs/reference/frontmatter-full.md to reflect the deprecation (or replace with dispatch-repository)
• Add engine.extensions section to docs/src/content/docs/reference/frontmatter.md (supported by schema but missing from concise reference)

Files Affected

• docs/src/content/docs/reference/engines.md
• docs/src/content/docs/reference/frontmatter.md
• docs/src/content/docs/reference/frontmatter-full.md

Success Criteria

• antigravity engine appears in engine reference docs
• No deprecated dispatch_repository examples in docs (replaced with dispatch-repository or annotated as deprecated)
• engine.extensions field documented in frontmatter reference
• Schema consistency check reports 0 documentation gaps for these items

Source

Extracted from [Schema Consistency] Schema Consistency Check - 2026-07-16 and [Schema Consistency] Schema Consistency Check - 2026-07-17

Priority

Medium — Users can successfully use features that docs don't mention; deprecated examples actively mislead users

🔍 Task mining by Discussion Task Miner - Code Quality Improvement Agent · 62.6 AIC · ⌖ 7.51 AIC · ⊞ 7K · ◷

• expires on Jul 18, 2026, 11:14 AM UTC-08:00

[github-actions]

This issue was automatically closed because it expired on 2026-07-18T19:14:37.974Z.

Closed by Workflow