Adds a queue-driven `MockLlmClient` that implements the `LlmClient` trait
by replaying canned per-turn `StreamEvent` vectors and capturing every
outgoing `MessageRequest`. The mock lives at the trait boundary so it
stays decoupled from the concrete reqwest plumbing inside `DeepSeekClient`,
and surfaces builders (`canned::*`) for the common event shapes (text
delta, thinking delta, tool_use start, input JSON delta, message delta).
Wires a new `--record <DIR>` flag into `deepseek eval` that appends one
JSON Lines fixture line per step to `<DIR>/<scenario>.jsonl`. The format
is documented at the top of `eval.rs` and is the storage shape the mock
will replay from.
`crates/tui/src/llm_client.rs` becomes `crates/tui/src/llm_client/mod.rs`
to host the new submodule cleanly. The trait shape is unchanged.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Hunter Bown
0626bc80c0