Remove internal-only bundled skills and mock helpers (#376)

* Remove internal-only bundled skills and mock rate-limit behavior

This takes the next planned Phase C-lite slice by deleting bundled skills
that only ever registered for internal users and replacing the internal
mock rate-limit helper with a stable no-op external stub. The external
build keeps the same behavior while removing a concentrated block of
USER_TYPE-gated dead code.

Constraint: Limit this PR to isolated internal-only helpers and avoid bridge, oauth, or rebrand behavior
Rejected: Broad USER_TYPE cleanup across mixed runtime surfaces | too risky for the next medium-sized PR
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: The next cleanup pass should continue with similarly isolated USER_TYPE helpers before touching main.tsx or protocol-heavy code
Tested: bun run build
Tested: bun run smoke
Tested: bun run verify:privacy
Tested: bun run test:provider
Tested: bun run test:provider-recommendation
Not-tested: Full repo typecheck (upstream baseline remains noisy)

* Align internal-only helper removal with remaining user guidance

This follow-up fixes the mock billing stub to be a true no-op and removes
stale user-facing references to /verify and /skillify from the same PR.
It also leaves a clearer paper trail for review: the deleted verify skill
was explicitly ant-gated before removal, and the remaining mock helper
callers still resolve to safe no-op returns in the external build.

Constraint: Keep the PR focused on consistency fixes and reviewer-requested evidence, not new cleanup scope
Rejected: Leave stale guidance for a later PR | would make this branch internally inconsistent after skill removal
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: When deleting gated features, always sweep user guidance and coordinator prompts in the same pass
Tested: bun run build
Tested: bun run smoke
Tested: bun run verify:privacy
Tested: bun run test:provider
Tested: bun run test:provider-recommendation
Not-tested: Full repo typecheck (upstream baseline remains noisy; changed-file scan still shows only pre-existing tipRegistry errors outside edited lines)

* Clarify generic workflow wording after skill removal

This removes the last generic verification-skill wording that could still
be read as pointing at a deleted bundled command. The guidance now talks
about project workflows rather than a specific bundled verify skill.

Constraint: Keep the follow-up limited to reviewer-facing wording cleanup on the same PR
Rejected: Leave generic wording as-is | still too easy to misread after the explicit /verify references were removed
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: When removing bundled commands, scrub both explicit and generic references in the same branch
Tested: bun run build
Tested: bun run smoke
Not-tested: Additional checks unchanged by wording-only follow-up

---------

Co-authored-by: anandh8x <test@example.com>

src/coordinator/coordinatorMode.ts

@@ -111,7 +111,7 @@ export function getCoordinatorUserContext(
 export function getCoordinatorSystemPrompt(): string {
   const workerCapabilities = isEnvTruthy(process.env.CLAUDE_CODE_SIMPLE)
     ? 'Workers have access to Bash, Read, and Edit tools, plus MCP tools from configured MCP servers.'
-    : 'Workers have access to standard tools, MCP tools from configured MCP servers, and project skills via the Skill tool. Delegate skill invocations (e.g. /commit, /verify) to workers.'
+    : 'Workers have access to standard tools, MCP tools from configured MCP servers, and project skills via the Skill tool. Delegate skill invocations (e.g. /commit or project workflow skills) to workers.'
 
   return `You are Claude Code, an AI assistant that orchestrates software engineering tasks across multiple workers.