fix: list OpenCode as runtime with Task tool support in map-codebase

OpenCode has a `task` tool that supports spawning subagents, but
map-codebase workflow incorrectly listed it under "Runtimes WITHOUT
Task tool". This caused the agent to skip parallel mapping and fall
back to sequential mode, wasting tokens when it self-corrected.

Move OpenCode to the "with Task tool" list and clarify that either
`Task` or `task` (case-insensitive) qualifies. Add regression test.

Fixes #1316

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/init.test.cjs

@@ -950,6 +950,19 @@ describe('cmdInitMapCodebase', () => {
     assert.deepStrictEqual(output.existing_maps, []);
     assert.strictEqual(output.codebase_dir_exists, true);
   });
+
+  test('map-codebase workflow lists OpenCode as having Task tool support (#1316)', () => {
+    const workflow = fs.readFileSync(
+      path.join(__dirname, '..', 'get-shit-done', 'workflows', 'map-codebase.md'), 'utf8'
+    );
+    // OpenCode must appear in the "with Task tool" line, not the "WITHOUT" line
+    const withLine = workflow.split('\n').find(l => l.includes('Runtimes with Task tool'));
+    const withoutLine = workflow.split('\n').find(l => l.includes('WITHOUT Task tool'));
+    assert.ok(withLine, 'workflow should have a "Runtimes with Task tool" line');
+    assert.ok(withoutLine, 'workflow should have a "WITHOUT Task tool" line');
+    assert.ok(withLine.includes('OpenCode'), 'OpenCode must be listed under runtimes WITH Task tool');
+    assert.ok(!withoutLine.includes('OpenCode'), 'OpenCode must NOT be listed under runtimes WITHOUT Task tool');
+  });
 });
 
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