feat: docs/ carries the operator's how-to guides, a configuration reference and the architecture and telemetry explanations carved out of README.md, INSTALL.md, INSTALL-MCP.md and EVALS.md; the last two retired (#190)

Files changed:
- .gitea/workflows/ci.yml
- .gitignore
- .vibe/hooks.toml
- AGENTS.md
- CHANGES.md
- EVALS.md
- INSTALL-MCP.md
- INSTALL.md
- README.md
- VERSION
- docs/dev/development.md
- docs/explanation/README.md
- docs/explanation/architecture.md
- docs/explanation/language-boundaries.md
- docs/explanation/telemetry-and-evaluation.md
- docs/how-to/README.md
- docs/how-to/browse-with-obsidian.md
- docs/how-to/capture-repository-docs.md
- docs/how-to/export-guidelines.md
- docs/how-to/ingest-a-source.md
- docs/how-to/maintain-the-wiki.md
- docs/how-to/query-the-wiki.md
- docs/how-to/run-the-weekly-review.md
- docs/how-to/set-up-the-mcp-server.md
- docs/how-to/trace-and-score-sessions.md
- docs/how-to/troubleshoot.md
- docs/how-to/update-an-instance.md
- docs/reference/README.md
- docs/reference/commands/distribution-and-versioning.md
- docs/reference/commands/instance-health.md
- docs/reference/commands/raw-material-and-uploads.md
- docs/reference/commands/telemetry.md
- docs/reference/commands/types-instructions-and-docs.md
- docs/reference/configuration.md
- instructions/dev/dev-setup.md
- instructions/dev/doc-pull-through.md
- instructions/dev/stack-build/SKILL.md
- instructions/dev/testing-conventions.md
- instructions/dev/version-parts.md
- instructions/setup-instance.md
- instructions/upgrade-instance.md
- reports/CONTRACT.md
- tools/.coveragerc
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/doctor.py
- tools/chemenu/commands/eval_cmd.py
- tools/chemenu/commands/git_publish.py
- tools/chemenu/commands/upload_cmd.py
- tools/chemenu/commands/version_cmd.py
- tools/chemenu/evals/__init__.py
- tools/chemenu/evals/scorecard.py
- tools/chemenu/evals/trajectory.py
- tools/chemenu/telemetry/policy.py
- tools/chemenu/tests/test_dist_cmd.py
- tools/chemenu/tests/test_git_publish.py
- tools/chemenu/tests/test_instructions_shell.py
- tools/chemenu/tests/test_pipeline_l0.py
- tools/chemenu/toc.py

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SnAJ7Z3CpVD3PRbN73QtU2

instructions/upgrade-instance.md

@@ -95,8 +95,8 @@ a further checkout of this one ([bootstrap.md](bootstrap.md)).
    beside it before unpacking, and refuses one that does not match. A tarball must unpack to
    exactly one top-level directory. The checksum comes from the same host as the archive, so it catches a
    damaged transfer, not a compromised host - who is trusted to publish releases is the
-   operator's decision, made before this file starts ([INSTALL.md](../INSTALL.md) § "Version und
-   Updates").
+   operator's decision, made before this file starts
+   ([update-an-instance.md](../docs/how-to/update-an-instance.md)).
 
 5. **Dry-run the swap and read all four counts:**
 
@@ -293,4 +293,4 @@ own - see the second paragraph. Anything about
 [migrate-corpus.md](migrate-corpus.md) § "Writing the migration document".
 
 What a human decides before any of this starts - which release, whether to take it at all, where
-the tarball comes from - is [INSTALL.md](../INSTALL.md) § "Version und Updates".
+the tarball comes from - is [update-an-instance.md](../docs/how-to/update-an-instance.md).