Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/ack-id/src/a2a/service-endpoints.test.ts`:
- Around line 19-26: Rename the test title to use the approved assertive
pattern: change the it(...) description for the test that calls
createAgentCardServiceEndpoint with DID "did:web:example.com:agents:my-agent" to
an assertive form such as "returns an id with `#agent-card` for colon-separated
DID paths" (or another "creates/returns/throws/requires" phrasing); keep the
test body and expectations
(expect(endpoint.id).toBe("did:web:example.com:agents:my-agent#agent-card"))
unchanged so only the test name is updated.

In `@packages/ack-id/src/a2a/sign-message.test.ts`:
- Around line 45-151: Rename the test titles to use assertive verbs
(creates/returns/throws/requires) so they follow the project's naming
convention: update the it(...) strings in tests referencing
createA2AHandshakePayload ("echoes the request nonce..." → "returns the request
nonce and creates a new reply nonce"), createA2AHandshakeMessageFromJwt ("wraps
a JWT..." → "returns an A2A data-part message containing a JWT" and "respects
the role parameter" → "returns the provided role"), createSignedA2AMessage
("produces a JWT signature..." → "creates a JWT signature and attaches it to
message metadata", "preserves original message content..." → "returns original
message content alongside the signature", "merges the signature..." → "creates
merged metadata without clobbering existing fields"), and
createA2AHandshakeMessage ("signs a credential handshake and returns the
nonce..." → "creates a signed credential handshake and returns the nonce",
"embeds the signed JWT..." → "returns a message embedding the signed JWT"); keep
the test logic and assertions unchanged, only change the human-readable it(...)
description strings.

In `@packages/ack-id/src/a2a/verify.test.ts`:
- Around line 40-250: The tests use non-assertive "it(...)" titles; rename each
test title in this suite to use the mandated assertive prefixes (creates...,
throws..., requires..., or returns...) so they conform to the guideline.
Specifically update the it(...) descriptions in the verifyA2AHandshakeMessage
and verifyA2ASignedMessage blocks (tests referencing verifyA2AHandshakeMessage,
verifyA2ASignedMessage, mockValidSignature, handshakeMessage, signedMessage,
unsignedMessage) — e.g. change "extracts issuer, nonce, and credential from a
valid handshake" to "returns issuer, nonce, and credential from a valid
handshake", "verifies the JWT with audience=self and issuer=counterparty" to
"requires JWT verification with audience=self and issuer=counterparty" or
similar, and similarly convert "rejects ..." to "throws ..." where appropriate;
apply consistent pattern across all test titles.

---

Nitpick comments:
In `@packages/ack-id/src/a2a/random.test.ts`:
- Around line 5-6: The current uuidPattern only checks generic UUID shape;
tighten it to assert UUIDv4 version and RFC-variant bits so tests for
generateRandomJti and generateRandomNonce validate v4 UUIDs. Replace the pattern
used in uuidPattern with one that enforces a '4' in the version position and one
of [89ab] in the variant position (e.g. pattern matching
...-4...-[89ab]...-...), keeping case handling consistent with the rest of the
tests.

In `@packages/ack-id/src/a2a/verify.test.ts`:
- Around line 84-112: The tests in verify.test.ts currently only assert that
malformed messages cause verifyA2AHandshakeMessage to reject, but they don’t
assert that JWT verification (verifyJwt) is not invoked; update the table-driven
test to mock or spy on the verifyJwt function used by verifyA2AHandshakeMessage
and add a non-call assertion (e.g., expect(verifyJwt).not.toHaveBeenCalled())
after the await expect(...).rejects.toThrow() so the test proves schema
validation occurs before any JWT verification. Make sure the mock/spy targets
the same symbol imported/used by verifyA2AHandshakeMessage (verifyJwt) so the
assertion reliably detects no calls.