fix: resolve simple triaged GitHub bugs

[code-yeongyu]

Summary

• Return a clear subagent_type is required error for malformed call_omo_agent calls instead of throwing.
• Normalize bare JSON Schema $ref values to #/$defs/... pointers.
• Treat gh as installed when Bun.which misses it but gh --version succeeds.

Verification

• bun test src/tools/call-omo-agent/tools.test.ts src/plugin/normalize-tool-arg-schemas.test.ts src/cli/doctor/checks/tools-gh.test.ts
• bun run typecheck
• bun run build
• bun run script/run-ci-tests.ts
• Manual Bun driver scripts for all three changed surfaces

Notes

• Plain bun test still fails when run all-at-once because several existing tests require isolated execution; the project CI split runner passes.

---

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• Let Codesmith autofix CI failures and bot reviews

[cubic-dev-ai]

1 issue found across 6 files

Confidence score: 3/5

• There is a concrete regression risk in src/plugin/normalize-tool-arg-schemas.ts: $ref normalization may rewrite valid relative URI refs (with path/fragment) into #/$defs/..., which can break schema link resolution at runtime.
• The reported severity/confidence (6/10, 8/10) suggests this is more than a cosmetic issue, so the merge carries some user-facing risk unless this behavior is constrained or fixed.
• Pay close attention to src/plugin/normalize-tool-arg-schemas.ts - ensure relative $ref values with paths/fragments are preserved correctly during normalization.

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/plugin/normalize-tool-arg-schemas.ts">

<violation number="1" location="src/plugin/normalize-tool-arg-schemas.ts:51">
P2: `$ref` normalization rewrites valid relative URI references (with path/fragment) into `#/$defs/...`, which can corrupt schema links.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: $ref normalization rewrites valid relative URI references (with path/fragment) into #/$defs/..., which can corrupt schema links.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/plugin/normalize-tool-arg-schemas.ts, line 51:

<comment>`$ref` normalization rewrites valid relative URI references (with path/fragment) into `#/$defs/...`, which can corrupt schema links.</comment>

<file context>
@@ -47,6 +47,14 @@ function isRecord(value: unknown): value is Record<string, unknown> {
 }
 
+function normalizeJsonSchemaRef(value: string): string {
+  if (value.startsWith("#") || value.includes(":") || value.startsWith("/")) {
+    return value
+  }
</file context>