docs(claude): refresh .claude/ rules and add testing guide

[MatiasOS]

Description

Refreshes the .claude/ rules directory to reflect the current state of the codebase. Adds a new testing.md documenting the Vitest + Playwright model (projects, suites, mocking, CI mapping), expands the architecture and commands docs with details that have drifted (adapter coverage, the worker/ companion sub-project, additional npm scripts), and brings the top-level CLAUDE.md quick-reference in line.

Related Issue

N/A — documentation maintenance.

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactoring
• Performance improvement
• Other (please describe):

Changes Made

.claude/rules/testing.md (new)

• Documents the two-layer test setup: Vitest for unit tests and Playwright for e2e.
• Describes the two Playwright projects (chromium for live RPC, mocked for hermetic specs under e2e/tests/shared/mocked/).
• Maps the e2e/tests/ directory tree by chain family (bitcoin/, eth-mainnet/, evm-networks/, shared/, solana/, testnets/).
• Lists per-network runner scripts, debug/UI modes, and the corresponding GitHub Actions workflows so contributors know which CI signal a given suite produces.

.claude/rules/patterns.md

• Adds a "Testing Patterns" section summarising the hermetic-vs-live rule of thumb: deterministic specs that exercise RPC strategy / inconsistency flags / errors belong under shared/mocked/; chain-specific live specs go under eth-mainnet/, evm-networks/, etc.

.claude/rules/architecture.md

• Enumerates every adapter with its chain IDs, splitting out BNBAdapter (56/97), PolygonAdapter (137/80002), and SolanaAdapter, and listing Arbitrum/OP-Stack testnets.
• Points at src/services/adapters/adaptersFactory.ts and documents the three factory entry points (createAdapter, createBitcoinAdapter, createSolanaAdapter).
• Adds a "Companion Sub-Project: worker/" section describing the Hono-based RPC proxy, its multi-platform deployment (Cloudflare Workers / Vercel Edge / Deno Deploy), and the redundancy/failover behaviour from the frontend.

.claude/rules/commands.md

• Documents previously-missing scripts: build:development, plain build, preview, check, audit (with a note on audit.sh generating a temporary lockfile because the repo uses Bun), and publish:dist.
• Adds focused e2e runners (test:e2e:eth-mainnet, test:e2e:evm-networks), the --project=mocked command, and a cross-link to the new testing.md.

.claude/CLAUDE.md

• Pins the Bun version (1.1.0) and clarifies that documented npm run commands work because they invoke package.json scripts (bun run is equivalent).
• Adds quick-reference rows for check, unit/e2e test runners, and npm run dev.
• Registers testing.md in the modular instructions index.

Screenshots (if applicable)

N/A — documentation-only change.

Checklist

• I have run npm run format:fix and npm run lint:fix (no-op for .md files — Biome is scoped to src/** .ts/.tsx/.json)
• I have run npm run typecheck with no errors (no source changes)
• I have run tests with npm run test:run (no source changes)
• I have tested my changes locally (docs reviewed against current code: adapter factory, package.json scripts, Playwright config, e2e tree)
• I have updated documentation if needed (this PR is the documentation update)
• My code follows the project's architecture patterns

Additional Notes

• Targets dev per the patch-release workflow.
• Split into two commits for reviewability: one adds the testing rules and the references to them; the other expands the existing commands/architecture/quick-reference docs.
• No source code changes, so the type-check / test / lint checkboxes above are effectively no-ops — included for completeness.

[github-actions]

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