feat: add CI/CD workflows with NuGet and npm publishing

[antosubash]

Summary

• Add two-workflow CI/CD pipeline: ci.yml (lint, build, test) and release.yml (version bump, NuGet publish, npm publish)
• Unified versioning from version.json starting at 0.0.1 — all packages share one version
• Auto patch bump on every merge to main; manual workflow_dispatch for minor/major
• Publish 10 NuGet packages (all framework/ projects) and 3 npm packages (@simplemodule/client, @simplemodule/ui, @simplemodule/theme-default)
• Add professional READMEs for all 13 packages (landing pages for nuget.org and npmjs.com)
• Centralize packaging config in framework/Directory.Build.props

Changes

• version.json — new, starting at 0.0.1
• .github/workflows/ci.yml — rewritten with lint job, frontend build, concurrency groups
• .github/workflows/release.yml — new, version bump + NuGet/npm publish
• Directory.Build.props — NuGet metadata (Authors, License, RepositoryUrl, etc.)
• framework/Directory.Build.props — new, centralizes IsPackable + README packaging
• framework/*/*.csproj — package descriptions, PrivateAssets on source generators
• packages/*/package.json — removed "private": true for publishable packages
• 13 README.md files — NuGet and npm package landing pages

Required secrets

Secret	Purpose
NUGET_API_KEY	NuGet.org API key
NPM_TOKEN	npm access token with publish scope

Test plan

• Verify CI workflow runs lint, build, and test jobs on PR
• Add NUGET_API_KEY and NPM_TOKEN secrets to repo settings
• Merge to main and verify release workflow triggers with patch bump
• Verify packages appear on nuget.org and npmjs.com
• Test manual workflow_dispatch with minor bump

🤖 Generated with Claude Code