Add one-command Meeting Lab benchmark runner

Add a repository-native runner for reproducible Meeting Lab benchmark runs on machines without Codex.

The runner:

- validates normalized Whisper input and Meeting Context
- checks Ollama availability and the requested model
- rejects preloaded Ollama models by default for clean benchmarks
- supports an explicit --allow-loaded-models override
- uses the selected production configuration:
  - qwen3.5:9b
  - target_chars=4500
  - max_chars=5500
  - min_chars=2500
  - overlap_blocks=0
  - think=false
  - temperature=0
  - num_ctx=32768
- executes the complete current pipeline
- creates unique benchmark output directories
- preserves artifacts up to failure
- records runtime, environment and validation metadata
- writes working_protocol.md only when the renderer contract passes

Add focused mocked tests and Linux-first setup documentation for the AI-PC.
The runner does not include Whisper execution.

README.md

@@ -192,6 +192,33 @@ PYTHONPATH=src .venv/bin/python -m meeting_lab.consolidation.consolidate_facts \
 
 Die eigentliche Ausgabeerzeugung ist bewusst der letzte Verarbeitungsschritt.
 
+Ein kompletter repository-nativer Referenzlauf fuer das Progeo-Benchmark kann
+auf dem Linux AI-PC ohne Codex mit einem Befehl gestartet werden:
+
+```text
+python scripts/run_meeting.py \
+  --input samples/real_live/progeo_meeting/progeo_whispercpp_vulkan_turbo_trimmed_converted.json \
+  --context samples/real_live/progeo_meeting/meeting_context.yaml \
+  --model qwen3.5:9b \
+  --benchmark-label progeo_ai_pc
+```
+
+Die Linux-Einrichtung ist:
+
+```text
+python3 -m venv .venv
+source .venv/bin/activate
+python -m pip install --upgrade pip
+python -m pip install -e .
+ollama pull qwen3.5:9b
+ollama list
+ollama ps
+```
+
+`ollama ps` muss fuer den Referenzlauf leer sein. Details zu Voraussetzungen,
+Artefakten, Windows-Beispiel und Vergleich mit dem AI-PC stehen in
+`docs/run-meeting.md`.
+
 ---
 
 ## Lizenz