docs: Extract and organize CLAUDE.MD content, restructure documentation

This commit performs comprehensive documentation reorganization:

1. Extracted testing checklist from CLAUDE.MD to docs/standards/testing-checklist.md
   - Consolidated manual testing checklist
   - Added validation tools and resources
   - Created pre-release validation workflow

2. Streamlined CLAUDE.md to lightweight operational instructions
   - Python environment setup (uv)
   - Agent-developer protocol
   - Key documentation references
   - Removed redundant content (already in other docs)

3. Removed CLAUDE.MD (uppercase) - content was redundant
   - All content already exists in architecture/overview.md and projectplan docs
   - Only unique content (testing checklist) was extracted

4. Moved root documentation files to appropriate locations:
   - CONTAINER_IMPLEMENTATION_SUMMARY.md -> docs/reports/2025-11-19-container-implementation-summary.md
   - QUICKFIX-AUTH-LOOP.md -> docs/reports/2025-11-18-quickfix-auth-loop.md
   - TECHNOLOGY-STACK-SUMMARY.md -> docs/architecture/technology-stack-legacy.md
   - TODO_TEST_UPDATES.md -> docs/reports/2025-11-19-todo-test-updates.md

5. Consolidated design folders:
   - Moved all docs/designs/ content into docs/design/
   - Renamed PHASE-5-EXECUTIVE-SUMMARY.md to phase-5-executive-summary.md (consistent naming)
   - Removed empty docs/designs/ directory

6. Added ADR-021: IndieAuth Provider Strategy
   - Documents decision to build own IndieAuth provider
   - Explains rationale and trade-offs

Repository root now contains only: README.md, CLAUDE.md, CHANGELOG.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

CLAUDE.md

@@ -1,4 +1,44 @@
-- we use uv for python venv management in this project so commands involving python probably need to be run with uv
-- whenever you invoke agent-developer you will remind it to document what it does in docs/reports, update the changelog, and increment the version number where appropriate inline with docs/standards/versioning-strategy.md
-- when invoking agent-developer remind in that we are using uv and that any pyrhon commands need to be run with uv
-- when invoking agent-developer make sure it follows proper git protocol as defined in docs/standards/git-branching-strategy.md
+# Claude Agent Instructions
+
+This file contains operational instructions for Claude agents working on this project.
+
+## Python Environment
+
+- We use **uv** for Python virtual environment management
+- All Python commands must be run with `uv run` prefix
+- Example: `uv run pytest`, `uv run flask run`
+
+## Agent-Developer Protocol
+
+When invoking the agent-developer, always remind it to:
+
+1. **Document work in reports**
+   - Create implementation reports in `docs/reports/`
+   - Include date in filename: `YYYY-MM-DD-description.md`
+
+2. **Update the changelog**
+   - Add entries to `CHANGELOG.md` for user-facing changes
+   - Follow existing format
+
+3. **Version number management**
+   - Increment version numbers according to `docs/standards/versioning-strategy.md`
+   - Update version in `starpunk/__init__.py`
+
+4. **Follow git protocol**
+   - Adhere to git branching strategy in `docs/standards/git-branching-strategy.md`
+   - Create feature branches for non-trivial changes
+   - Write clear commit messages
+
+## Key Documentation References
+
+- **Architecture**: See `docs/architecture/overview.md`
+- **Implementation Plan**: See `docs/projectplan/v1/implementation-plan.md`
+- **Feature Scope**: See `docs/projectplan/v1/feature-scope.md`
+- **Coding Standards**: See `docs/standards/python-coding-standards.md`
+- **Testing**: See `docs/standards/testing-checklist.md`
+
+## Project Philosophy
+
+"Every line of code must justify its existence. When in doubt, leave it out."
+
+Keep implementations minimal, standards-compliant, and maintainable.