Document project architecture and development methodology

- add AGENTS.md with development and prompt-engineering rules
- add PROJECT_KNOWLEDGE.md summarizing current architecture and findings
- add CHANGELOG.md
- add ROADMAP.md
- establish experiments.md as the project's experiment log
- document Canonical Meeting Knowledge architecture
- document Output Views and Knowledge Objects
- capture accepted experimental results and engineering methodology

AGENTS.md

@@ -0,0 +1,124 @@
+# AGENTS.md
+
+Practical instructions for coding agents working in Meeting Lab.
+
+## Project Purpose
+
+Meeting Lab extracts and structures organizational knowledge from meeting
+recordings. It is an experimental local discussion analyzer, not merely a
+one-step meeting-protocol generator.
+
+Successful approaches may later move into the Meeting Assistant project.
+
+## Current Pipeline
+
+Current and intended flow:
+
+```text
+Audio
+-> Whisper
+-> cleanup
+-> normalization
+-> chunking
+-> local chunk extraction
+-> consolidation
+-> Canonical Meeting Knowledge
+-> Output Views
+```
+
+Status:
+
+- Implemented: Whisper JSON cleanup script, normalization, technical chunking,
+  local chunk extraction, interim Markdown protocol builder.
+- Experimental/prototype: topic segmentation and review tooling.
+- Planned: consolidation, Canonical Meeting Knowledge implementation, final
+  Output Views.
+
+## Architectural Principles
+
+- Canonical Meeting Knowledge is the intended semantic source of truth.
+- Working Protocol / Arbeitsprotokoll, Distribution Protocol /
+  Verteilerprotokoll and Knowledge Objects / Wissensdatenbankeintrag are
+  parallel output views.
+- Output views must not silently change meaning. They may select, condense or
+  render information for an audience, but not invent new semantics.
+- Extraction, consolidation, synthesis and rendering are separate concerns.
+- Prefer small, testable processing stages over one monolithic LLM prompt.
+- Current extraction strategy is one normalized chunk per LLM call.
+- Do not expand context windows or redesign the extraction strategy without an
+  explicit experiment.
+- Deterministic stages should remain deterministic where possible.
+
+## Prompt Engineering Rules
+
+The Gold Standard corpus is the reference specification. Follow Rules 1-11 from
+`tests/gold/PROMPT_ENGINEERING_METHODOLOGY.md`:
+
+1. Make only one prompt change per iteration.
+2. Optimize only one target gold test case at a time.
+3. Validate every prompt modification immediately.
+4. Accept a prompt change only if it improves the target and causes no
+   regressions in previously passing gold tests.
+5. Never modify `expected.json` merely to make a prompt pass.
+6. Prompt engineering edits prompt files only; Python code changes require a
+   separate explicit task.
+7. Maintain a prompt evolution log for every iteration.
+8. Stop arbitrary iterations if small changes do not improve the test; analyze
+   the root cause.
+9. Avoid gold-test overfitting. Prompt changes must generalize and must not
+   special-case one transcript.
+10. Stop after two consecutive non-improving prompt iterations and classify the
+    root cause.
+11. Verify whether the target gold test has objectively unique ground truth
+    before changing a prompt for unexpected behavior.
+
+Current documented Prompt Version 2 decision baseline:
+
+- `decision_simple`: passing
+- `decision_deferred`: passing
+- `decision_none`: passing
+
+## LLM Execution Safety
+
+- Never start a full multi-chunk LLM run unless explicitly requested.
+- Before any LLM run, state the model, inputs, expected LLM-call count and
+  output location.
+- Do not retry LLM calls automatically unless explicitly allowed.
+- Do not download models automatically.
+- Prefer small-scope validation runs.
+- Never use generated output as committed source data.
+- Preserve raw model responses when diagnosing parser or truncation failures.
+- Do not run Ollama from unit tests.
+
+## Development Rules
+
+- Make small, focused changes.
+- Preserve the existing architecture unless a redesign is explicitly requested.
+- Add regression tests for bugs.
+- Run non-LLM tests before committing when code changes are made.
+- Do not commit generated transcripts, audio, extraction JSON, protocol output
+  or temporary files.
+- Report files changed, tests run and assumptions.
+- Do not commit or push unless explicitly requested.
+
+## Repository Conventions
+
+- `README.md`: project overview and current high-level status.
+- `docs/`: architecture, pipeline, data model and output-view documentation.
+- `prompts/`: extraction and segmentation prompts. Treat prompt edits as
+  controlled experiments.
+- `tests/gold/`: Gold Standard corpus and semantic specification for extraction
+  behavior.
+- `scripts/`: command-line support scripts such as Whisper cleanup and gold
+  test execution.
+- `src/meeting_lab/normalization/`: deterministic transcript cleanup.
+- `src/meeting_lab/chunking/`: technical chunk creation; chunks are not topics.
+- `src/meeting_lab/segmentation/`: experimental topic segmentation tooling.
+- `src/meeting_lab/extraction/`: local LLM extraction flow and category
+  extractor modules.
+- `src/meeting_lab/consolidation/`: planned consolidation area.
+- `src/meeting_lab/protocol/`: interim protocol rendering.
+- `src/meeting_lab/models/`: current lightweight data models.
+- `samples/`: sample inputs and generated/experimental artifacts; do not treat
+  sample output as canonical source data.
+