Refactor: Remove unused Whisper variants

This commit removes the `whisper_variant` and `whisper_hotwords_variant`
fields from the `run_id` generation and the `print_meta_summary`
function.

These variants are no longer used as the project is shifting focus to
LLM-based generation. The `run_full_case.rs` example has also been
updated to reflect this change.

tests/fixtures/dictations/README.md

@@ -12,7 +12,6 @@ Per fixture, three files share a common stem:
 |------------------------|----------|-------------------------------------------------------------------|
 | `<name>.m4a`           | yes      | Raw AAC recording as produced by `scripts/dictate.sh` / the watch |
 | `<name>.expected.txt`  | yes      | Golden transcript, hand-reviewed — the regression target          |
-| `<name>.hotwords.txt`  | no       | One-line hotwords list if the fixture is meant to test Fachvokabular |
 | `<name>.notes.md`      | no       | Short description: what this case exercises, any gotchas          |
 
 ## Naming convention
@@ -24,8 +23,7 @@ Per fixture, three files share a common stem:
 - `ortho_knie_meniskus`
 - `psych_ptbs_flashbacks`
 
-The prefix encodes the medical domain so we can group by specialty when we
-start per-user hotwords tuning.
+The prefix encodes the medical domain so we can group by specialty.
 
 ## Adding a new fixture
 
@@ -36,11 +34,9 @@ start per-user hotwords tuning.
 4. Extract the transcript from the recording metadata sidecar:
    `jq -r '.transcript.text' $DATA_PATH/<slug>/open/<case_id>/<timestamp>.json`
    → write it to `tests/fixtures/dictations/<name>.expected.txt`.
-5. **Review the transcript** — fix any Whisper errors by hand. This is the
+5. **Review the transcript** — fix any ASR errors by hand. This is the
    golden reference; accept nothing that is actually wrong.
-6. If the fixture tests Fachvokabular, add `<name>.hotwords.txt` with the
-   domain-specific words, one space-separated line.
-7. Commit all three/four files together.
+6. Commit the files together.
 
 ## What not to commit here