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.

tests/plan-review-convergence.test.cjs

@@ -179,13 +179,6 @@ describe('plan-review-convergence command source (#2306)', () => {
     );
   });
 
-  test('command has Copilot runtime_note for AskUserQuestion fallback', () => {
-    assert.ok(
-      command.includes('vscode_askquestions'),
-      'must document vscode_askquestions fallback for Copilot compatibility'
-    );
-  });
-
   test('--codex is the default reviewer when no flag is given AND review.default_reviewers is unset (#2315)', () => {
     // #2315: a bare invocation now respects review.default_reviewers per
     // ADR-0011. The command must document that --codex is the default ONLY