fix(core): keep stdout pure when -o json/yaml/csv is requested - #99

…sweep) (#101)

Last command in the `-o json` sweep started by #97, plus the review
follow-ups that came out of it.

#97 fixed **requests, read, models, projects, members, usage, billing**
— but `keys` wasn't in that sweep, so it was left as the one account
command whose stdout still broke pipes:

```console
$ dg -o json keys | jq -r '.keys[0].key_id'
jq: parse error: Invalid numeric literal at line 1, column 9
```

`Fetching API keys...` and the Rich table were going to stdout ahead of
the JSON.

## The keys fix — same pattern as the merged seven

- `status_console` for progress, errors and the empty-state notice, so
chrome never touches stdout
- Human rendering gated on `get_output_format() == "default"`: the list
table, created-key details, key details, and both dry-run summaries

The created key's **secret is unaffected** — it already travels in
`KeysResult.created_key.key`, so json/yaml/csv callers still receive it;
only the human echo is suppressed. There's a test asserting exactly
that.

## Review follow-ups

Reviewing the above turned up four more defects. All predate this
branch, but three of them sit in code it touches and all four make "`-o
json` keeps stdout parseable" true only in the narrow case, so they're
fixed here rather than deferred.

**`dg keys --create --dry-run` never ran.** `handle` read `project_id`
and `dry_run` with `.get()` and then forwarded `**kwargs` alongside
them, so every argument arrived twice and Python raised `got multiple
values for argument 'project_id'` before the body started — swallowed
into an error result, exit 0. The dry-run gating added here was
unreachable, and this PR's original "known limitation" note described
behaviour that path never had. Popping both fixes it; fixing only
`dry_run` just exposes the `project_id` collision behind it.

**Failures exited 0.** `main.py` caught `SystemExit` and discarded the
code, so no command could ever signal failure — including the auth-guard
failure that already raised `SystemExit(1)`. `if dg -o json keys; then`
took the success branch on a failed call. The code is now carried
through the post-run notifications and re-raised, and `BaseCommand` maps
status to exit code in one table, matching the contract already
published in `llms-full.txt` (`0 = success, 1 = error, 2 = user
interrupt`): `error` → 1, `cancelled` → 2, everything else → 0. Exiting
0 on failure violated that documented contract, so this restores
published behaviour rather than introducing a new one — no docs change
needed.

**`-o yaml` and `-o csv` silently deleted user data.** Both printed
through Rich, which treats square brackets as style markup and removes
them — a key comment of `[ci] runner` came out as `runner`, no error.
Rich also hard-wrapped at the console width, injecting newlines into the
middle of a csv field. Both now write the payload verbatim (markup,
highlighting and wrapping off), still via `console` so `--quiet` keeps
working. The JSON path was already safe (`print_json` escapes rather
than interprets) and is untouched.

**`dg keys --delete ID` without `--yes` deleted nothing and blamed the
user.** `BaseCommand.confirm` returns its default whenever any parameter
came from the command line, and `--delete KEY_ID` is itself such a
parameter — so the prompt was unreachable and the command always
returned `Cancelled by user` without asking or calling the API. It now
prompts on stderr when someone is there to answer (stderr, so `-o json`
stdout stays clean), and returns a usage error naming `--yes` when
nobody is.

Also: `get_status_console()` in core replaces the eight per-command
`Console(stderr=True)` declarations. A per-command console silently
missed core's agentic no-color settings, and a new command reaching for
a bare `Console()` is exactly how `keys` regressed in the first place —
this makes it correct by default.

## Verification

| check | result |
|---|---|
| `dg -o json keys \| jq -r '.keys[0].key_id'` | returns the id ✓ (was a
parse error) |
| all 8 commands under `-o json` | keys, projects, models, usage,
requests, members, billing, read — all valid JSON on stdout ✓ (models is
77KB, so the wrapping fix holds at size) |
| `-o yaml` / `-o csv` for keys | valid, and bracketed values now
survive verbatim ✓ |
| chrome under `-o json` | still on stderr ✓ |
| human output | unchanged under a pty ✓ |
| `keys --create --dry-run` | reports `dry_run`, calls nothing ✓ (was a
TypeError) |
| `keys --delete ID` without `--yes` | usage error naming `--yes`, exit
1, no API call ✓ |
| exit codes | error → 1, cancelled → 2,
success/dry_run/`--help`/`--version` → 0, unknown command → 2 ✓ —
matches documented contract |
| tests | **1089 passed** (22 new), `ruff check` and `mypy` clean |

## Still open in #98

**#98 stays open for one item:** the promise that stdout auto-switches
to JSON *when piped*. `dg keys | jq` still gets the Rich table, because
the auto-switch (`setup_output`) sits behind `is_agentic()`, which needs
3+ soft signals; a plain pipe from an interactive shell scores 1.
Lowering that threshold changes what `dg <anything> | less` does for
every command, so it's a product decision rather than a bug fix —
deliberately not made here.

## Note on #99

#99 fixed the stdout bug with a central format-aware console before #97
landed. Now that #97 is merged, #99 is redundant and would conflict, so
I've closed it. Its one good idea — a shared status-console primitive
instead of per-command declarations — is implemented here as
`get_status_console()`.