"ajv compile --code-esm" outputs "error: parameter --code-esm is unknown"

Hi Folks. I'm trying to compile my schema to an ES module, but my command `npx ajv compile --code-esm -s src/schema.json -o src/validate.js` prints `error: parameter --code-esm is unknown` in spite of that option being documented at https://ajv.js.org/standalone.html :
> Set the code.esm (JS) value to true or pass the --code-esm (CLI) flag if you want ESM exported code.

Running that command without `--code-esm` prints `schema src/schema.json is valid` and generates `src/validate.js`, which shows my inputs are otherwise ok.

**What version of Ajv are you using? Does the issue happen if you use the latest version?**
- "ajv": "^8.12.0"
- "ajv-cli": "^5.0.0"
- npm --version # 9.5.0
- node --version # v18.15.0

Note that running `npm install --save-dev ajv` resulted in version 6.12.6 being installed (!), so I had to manually run `npm install --save-dev ajv@8.12.0` to get the latest version. Maybe I screwed something up?

**What results did you expect?**
Output with no error.