refactor: drop 12 runtimes, keep Claude, Codex, OpenCode, Cursor, ZCode, Antigravity

Removes kilo, kimi, kimi-code, copilot, windsurf, augment, trae, qwen, hermes,
cline, codebuddy and pi end to end: capability descriptors, installer branches
and converters (bin/install.js 14.9k -> 11.2k lines), TypeScript converters,
hook surfaces and runtime homes, review lanes qwen/kimi-code, the two pi
migrations, Kimi payload normalization in the hook guards, dead hostBehaviors
vocabulary, launcher home probes, fixtures, runtime-specific tests and the
prose that presented them as supported.

Installer output for the six kept runtimes is byte-identical to before the
prune. The Kimi tool-vocabulary tests in workflow-guard, read-guard and
read-injection-scanner are left in place pending a decision.

docs/manual-update.md

@@ -33,12 +33,8 @@ Replace `--claude` with the flag for your runtime:
 |---|---|
 | Claude Code | `--claude` |
 | OpenCode | `--opencode` |
-| Kilo | `--kilo` |
 | Codex | `--codex` |
-| Copilot | `--copilot` |
 | Cursor | `--cursor` |
-| Windsurf | `--windsurf` |
-| Augment | `--augment` |
 | All runtimes | `--all` |
 
 Use `--local` instead of `--global` for a project-scoped install.