fix(httpauth-jwt): WithJSONNumber in Verify, JSON errors in AuthMiddleware, bump httpauth v1.0.2 (#1)

Pass jwt.WithJSONNumber() to jwt.Parse in hmacSigner.Verify, rsaSigner.Verify, and
rsaPublicVerifier.Verify. JWT numbers (including permission bitmasks) are now decoded
as json.Number instead of float64 — exact parsing for all integers including
math.MaxInt64 (the ADMIN wildcard mask). Float64 would round MaxInt64 to 2^63 and
overflow back to math.MinInt64 on cast to int64.

AuthMiddleware now calls httpauth.WriteJSONError for all 401 responses instead of
http.Error. Standardizes the error format across the full httpauth-* middleware stack:
AuthMiddleware (httpauth-jwt), EnrichmentMiddleware, and AuthzMiddleware (httpauth)
all produce {"code":"UNAUTHENTICATED"|"PERMISSION_DENIED"|"INTERNAL","message":"..."}.

Update two existing tests (TestIssueTokenPair_CustomClaims,
TestRefreshTokenPair_CustomClaimsInNewToken) to assert json.Number instead of float64
— they were correct before WithJSONNumber, now reflect the actual decoded type.

Add TestVerify_JSONNumberPreservesMaxInt64: issues a token with math.MaxInt64 as a
bitmask, verifies it, and asserts the decoded value is exactly math.MaxInt64 via
json.Number.Int64() — proving no float64 round-trip occurs.

Add TestAuthMiddleware_UnauthorizedJSON: asserts the 401 response is
Content-Type: application/json with body {"code":"UNAUTHENTICATED","message":"..."}.

Bump httpauth dependency to v1.0.2.

Reviewed-on: #1
Co-authored-by: Rene Nochebuena Guerrero <rene@nochebuena.dev>
Co-committed-by: Rene Nochebuena Guerrero <rene@nochebuena.dev>

go.mod

@@ -3,8 +3,11 @@ module code.nochebuena.dev/go/httpauth-jwt
 go 1.26
 
 require (
-	code.nochebuena.dev/go/httpauth v1.0.0
+	code.nochebuena.dev/go/httpauth v1.0.2
 	github.com/golang-jwt/jwt/v5 v5.2.1
 )
 
-require code.nochebuena.dev/go/rbac v1.0.0 // indirect
+require (
+	code.nochebuena.dev/go/rbac v1.0.0 // indirect
+	code.nochebuena.dev/go/xerrors v1.0.1 // indirect
+)