feat: add support for generating an mcpb package MCP-126

[nirinchev]

Proposed changes

This adds support for generating an .mcpb package (the new .dxt). I've tested it with Claude desktop on macOS and it worked just fine.

[Copilot]

Pull request overview

Adds support for building and publishing an .mcpb desktop-extension package for the MCP server, including CI automation and a packaging manifest.

Changes:

• Introduces an mcpb build/validate script plus a small unit test suite and vitest project wiring.
• Adds packaging/mcpb manifest/entrypoint/icon assets and keeps manifest version synced with package.json.
• Updates CI workflows to validate/build .mcpb and attach artifacts to GitHub releases.

Reviewed changes

Copilot reviewed 12 out of 15 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
vitest.config.ts	Adds a dedicated vitest project for the mcpb build-script tests.
src/transports/stdio.ts	Simplifies stdio runner startup by removing redundant local error handling.
scripts/updatePackageVersion.ts	Updates .mcpb manifest version alongside generated packageInfo.ts.
scripts/createMcpb.ts	Implements staging/install/pack flow for producing .mcpb artifacts.
scripts/createMcpb.test.ts	Adds initial unit tests around staging package.json generation.
pnpm-lock.yaml	Locks new dependencies (@anthropic-ai/mcpb, type-fest) and transitives.
packaging/mcpb/server/index.js	Adds the .mcpb server entrypoint that loads built dist output.
packaging/mcpb/manifest.json	Adds the .mcpb manifest (runtime, env wiring, user config schema).
packaging/mcpb/icon.png	Adds the .mcpb icon asset.
package.json	Adds build/validate scripts for .mcpb and required deps.
knip.json	Marks the .mcpb server entrypoint as an entry for unused-code scanning.
.prettierignore	Excludes the .mcpb manifest from prettier formatting.
.gitignore	Ignores .mcpb build output directories.
.github/workflows/publish.yml	Builds .mcpb during publish and attaches it to the GitHub release.
.github/workflows/mcpb.yml	Adds a workflow to validate/build .mcpb and optionally upload artifacts.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

[coveralls]

Coverage Report for CI Build 25228128689

Warning

No base build found for commit 949dbcd on main.
Coverage changes can't be calculated without a base build.
If a base build is processing, this comment will update automatically when it completes.

Coverage: 81.774%

Details

• Patch coverage: 3 uncovered changes across 1 file (0 of 3 lines covered, 0.0%).

Uncovered Changes

File	Changed	Covered	%
src/transports/stdio.ts	3	0	0.0%

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	3665
Covered Lines:	3190
Line Coverage:	87.04%
Relevant Branches:	2299
Covered Branches:	1687
Branch Coverage:	73.38%
Branches in Coverage %:	Yes
Coverage Strength:	172.77 hits per line

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💛 - Coveralls