docs: add Claude Code project guide and verified architecture reference

Contributor-friendly CLAUDE.md with setup, conventions, and architecture
overview. Comprehensive skills/architecture.md verified against actual
codebase covering all 31 source directories, 38+ exports, and major
subsystems (distributed, transactions, neural, CLI, MCP, COW, etc).

Remove CLAUDE.md from .gitignore since the new version is designed
for public contributors.

CLAUDE.md

@@ -0,0 +1,112 @@
+# Brainy - Claude Code Project Guide
+
+This file provides guidance for Claude Code (and human contributors) when working on the Brainy codebase.
+
+## Project Overview
+
+Brainy is a Universal Knowledge Protocol -- a Triple Intelligence database that combines vector similarity search, graph traversal, and metadata filtering into a single TypeScript library. Published as `@soulcraft/brainy` on npm under the MIT license.
+
+## Getting Started
+
+```bash
+npm install           # Install dependencies
+npm run build         # Build the project
+npm test              # Run test suite (Vitest)
+```
+
+## Architecture
+
+Full architecture reference: `.claude/skills/architecture.md`
+
+### Core Systems
+- **Storage** (`src/storage/`): Pluggable storage backends via StorageAdapter interface (`src/coreTypes.ts`)
+- **Vector Search** (`src/hnsw/`): HNSW approximate nearest neighbor search
+- **Graph Engine** (`src/graph/`): Relationship traversal with adjacency index and pathfinding
+- **Metadata Index** (`src/utils/metadataIndex.ts`): O(1) exact match, O(log n) range queries
+- **Triple Intelligence** (`src/triple/`): Unified query combining all three intelligence types
+- **Virtual Filesystem** (`src/vfs/`): Full VFS with semantic search
+
+### Type System
+- **NounType** (42 types): Entity classification -- Person, Concept, Collection, Document, Task, etc.
+- **VerbType** (127 types): Relationship types -- Contains, RelatedTo, PartOf, Creates, DependsOn, etc.
+- Defined in `src/types/graphTypes.ts`
+
+## Code Standards
+
+### TypeScript
+- Strict mode enabled
+- Target: ES2020, NodeNext module resolution
+- All new code must be TypeScript
+- Follow existing patterns -- read related code before writing
+
+### Quality
+- All code must compile without errors
+- All code must have working tests that exercise real behavior
+- No stub returns (`return {} as any`)
+- No incomplete implementations with TODO comments
+- If something can't be fully implemented, throw an explicit error rather than faking it
+
+### Verification Before Code Changes
+1. Check that interfaces and methods actually exist before using them
+2. Check that type properties are in the type definitions
+3. Run `npm test` -- tests must pass
+4. Run `npm run build` -- build must succeed
+
+### Testing
+- Framework: Vitest
+- Tests in `tests/` (unit, integration, benchmarks, comprehensive)
+- Use in-memory storage for speed where possible
+- Tests must exercise real behavior, not mock it
+- Benchmarks are in `tests/benchmarks/` (not tests/performance/)
+
+## Commit Conventions
+
+Use [Conventional Commits](https://www.conventionalcommits.org/):
+
+```
+feat: add new feature        (minor version bump)
+fix: resolve bug             (patch version bump)
+docs: update documentation   (patch version bump)
+perf: improve performance    (patch version bump)
+refactor: restructure code   (patch version bump)
+test: add/update tests       (patch version bump)
+```
+
+**Important:** Never use `BREAKING CHANGE` in commit messages. Major version bumps are manual decisions only (`npm run release:major`).
+
+## Release Process
+
+Fully automated via `scripts/release.sh`:
+
+```bash
+npm run release:dry          # Preview (no changes)
+npm run release:patch        # Bug fixes
+npm run release:minor        # New features
+npm run release:major        # Breaking changes (rare, manual decision)
+```
+
+The script: verifies clean git state, builds, tests, bumps version, updates CHANGELOG.md, commits, tags, pushes, publishes to npm, and creates a GitHub release.
+
+## Performance Claims
+
+When documenting performance characteristics:
+- **MEASURED**: Cite the test file and line number
+- **PROJECTED**: Clearly label as extrapolated from tested scale
+- Never claim a performance figure without context or evidence
+
+## Debugging
+
+When a bug persists through 2+ fix attempts, switch to systematic debugging:
+1. Add comprehensive logging at every step
+2. Test with production-like data
+3. Trace the complete execution path
+4. Check both library code and consumer code
+5. Verify with actual test execution before declaring fixed
+
+## Key Paths
+
+- Main class: `src/brainy.ts`
+- Public API: `src/index.ts` (38+ exports)
+- Storage interface: `src/coreTypes.ts`
+- Type definitions: `src/types/`
+- Strategy/planning docs: `.strategy/` (gitignored, not public)