chore(test): vitest harness, typecheck and test scripts (CLI-00)

[bayological]

What

Makes the gate able to judge work. Before this, package.json had only build, dev and
prepack, no test runner and no tests, so .skein/config.json's standard check proved the
code compiles and nothing more.

• Scripts: typecheck (tsc --noEmit -p tests/tsconfig.json), test (vitest run),
  test:watch (vitest).
• vitest as the only new dependency, a devDependency.
• tests/tsconfig.json — a typecheck-only project extending the root config, widening
  rootDir to the repo so src/, tests/ and vitest.config.ts are all checked. The root
  tsconfig.json is unchanged, so build and prepack still emit dist/ from src/
  alone; dist/ contains no tests/. It lives under tests/ because CLI-00 owns
  tests/** and not a new root file.
• 38 tests over the pure modules: tests/format.test.ts, tests/client.test.ts,
  tests/errors.test.ts. Suite runs in under a second.

No product behaviour changes. Nothing under src/ is touched.

Offline by construction

No test imports getMento, reaches an RPC, or constructs a wallet (AGENTS.md P1, P2). The
only SDK import is ChainId, so resolveChainId's expectations come from the SDK rather
than from memory (P3).

Left alone deliberately

parseAmount hands its input straight to BigInt(). tests/format.test.ts records today's
behaviour for "abc" (a raw SyntaxError, which handleError then prints verbatim) rather
than asserting the behaviour it should have. Fixing that is CLI-02.

Gate

SKEIN_GATE_RESULT task=CLI-00 base=origin/main status=PASS checks=brief:PASS,clean-tree:PASS,boundary:PASS,secrets:PASS,test-integrity:PASS,invariants:PASS,standard:PASS,e2e:PASS,accept:PASS

🤖 Generated with Claude Code

---

Note

Overview
Introduces a Vitest test harness so CI and local gates can run automated checks beyond compile-only validation. package.json gains typecheck (tsc --noEmit via tests/tsconfig.json), test, and test:watch, with vitest as the sole new devDependency.

tests/tsconfig.json extends the root config but widens scope to src/, tests/, and vitest.config.ts without changing build/prepack (still emit dist/ from src/ only). vitest.config.ts runs tests in Node and inlines @mento-protocol/mento-sdk so extensionless ESM imports resolve under Vite.

Adds 38 unit tests for pure helpers: resolveChainId in client, handleError messaging (with mocked process.exit), and formatAddress / parseAmount / formatTokenAmount. Tests stay offline—no RPC, wallets, or getMento. src/ is unchanged.

^{Reviewed by Cursor Bugbot for commit 00cd040. Bugbot is set up for automated code reviews on this repo. Configure here.}

[coderabbitai]

Navigate logical layers of code changes, visualize relationships, and explore their blast radius.

Note

Currently processing new changes in this PR. This may take a few minutes, please wait...

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Advanced

Run ID: f6c9fea9-a870-46b2-8e45-d74835a2824a

📥 Commits

Reviewing files that changed from the base of the PR and between fdb0456 and 00cd040.

⛔ Files ignored due to path filters (1)

• package-lock.json is excluded by !**/package-lock.json

📒 Files selected for processing (6)

• package.json
• tests/client.test.ts
• tests/errors.test.ts
• tests/format.test.ts
• tests/tsconfig.json
• vitest.config.ts

 _________________________
< I am the bug whisperer. >
 -------------------------
  \
   \   (\__/)
       (•ㅅ•)
       / 　 づ

✨ Finishing Touches

📝 Generate docstrings

• Commit to this branch
• Create a new PR

🧪 Generate unit tests (beta)

• Commit to this branch
• Create a new PR

---

_{Comment @coderabbitai help to get the list of available commands.}