Stabilize Meeting Lab pipeline for RC1 evaluation

This commit significantly improves the robustness and determinism of the Meeting Lab processing pipeline and establishes the first Release Candidate baseline for end-to-end evaluation.

Highlights

- BUG-009
  - Implement deterministic responsible-party validation
  - Normalize participant aliases using Meeting Context
  - Reject invalid responsible values (dates, locations, technical terms, projects, products, unknown entities)
  - Record structured responsibility validation metadata
  - Add focused regression tests

- BUG-010
  - Implement adaptive num_predict estimation for Semantic Consolidator
  - Eliminate JSON truncation caused by fixed output limits
  - Add deterministic source coverage repair
  - Preserve strict post-repair validation
  - Add regression tests

- BUG-011
  - Implement Working Protocol V2 renderer contract enforcement
  - Preserve raw renderer responses
  - Reject invalid protocol output instead of accepting malformed documents
  - Add deterministic cleanup for harmless formatting deviations
  - Add focused renderer regression tests

- Meeting Context
  - Validate Meeting Context V1
  - Integrate authoritative participant alias normalization

- Documentation
  - Update architecture documentation
  - Update output documentation
  - Update regression bug tracker

The pipeline now fails safely instead of silently accepting invalid intermediate or final artifacts.

Remaining work focuses primarily on extraction quality and semantic classification (decisions, action items, protocol faithfulness), rather than pipeline robustness.

docs/architecture.md

@@ -265,6 +265,11 @@ Deterministic Canonicalizer:
 - validates and normalizes extraction objects
 - assigns stable source references and IDs
 - normalizes category names and basic field structure
+- validates and normalizes action-item responsible fields against Meeting
+  Context when available: known participant and mentioned-person aliases are
+  normalized to canonical display names, while dates, locations, projects,
+  products, technical terms, generic process words and unknown free text are
+  cleared with a structured validation record
 - performs only safe deterministic cleanup
 - may group exact duplicates
 - preserves all source evidence
@@ -277,6 +282,12 @@ Semantic Consolidator:
 - V0 merges semantically equivalent fact items conservatively
 - V0 preserves source references and evidence
 - V0 validates that every source fact appears exactly once
+- V0 sizes its Ollama output budget from the actual fact payload instead of
+  using a fixed response cap for every meeting
+- V0 may apply deterministic source-coverage repair after valid model JSON is
+  parsed: duplicate source IDs are removed after their first occurrence, empty
+  groups are removed and missing source facts are restored as singleton groups
+  from canonicalized input before strict validation runs
 - V0 does not process non-fact categories semantically
 - later versions should group content by topic, mark contradictions and
   uncertainty, separate durable information from transient discussion and
@@ -295,6 +306,11 @@ It only reformulates the analysis results for a specific audience and purpose.
 Depending on the output and maturity of the implementation, a renderer may be
 deterministic, template-based or LLM-assisted.
 
+LLM-assisted renderers preserve raw model output separately and write the final
+output artifact only after deterministic contract validation succeeds. Renderer
+post-processing may remove non-semantic wrapper text, but must not fabricate
+missing semantic sections or relabel an invalid summary as a valid output view.
+
 The planned output products are:
 
 - Working Protocol (`working_protocol.md`, Arbeitsprotokoll)