feat: add support for relative endpoint URLs

[yeskunall]

Allow endpointUrl to be a relative path (e.g., /_umami) for proxied Umami instances served from a subdirectory. When using relative paths, the script src becomes relative and data-host-url is only set when explicitly provided.

Closes #139.

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Full disclosure: Opus 4.5 “one-shotted” this PR. By that, I mean I gave it the problem description, it came up with a plan after I shepherded it a bit, and then I let it run free. All tests passed locally, let’s wait for CI to finish.

[yeskunall]

@mschoeffmann wanna test this branch out? If not, I will probably setup pkg.pr.new and push a release that way.

Since this was wholly done by AI (other than me just guiding it), I’m not too comfortable making a release to NPM yet.

[Copilot]

Pull request overview

This PR adds support for relative endpoint URLs (e.g., /_umami) to enable proxied Umami instances served from a subdirectory. The implementation handles relative paths by generating relative script src attributes and conditionally setting data-host-url only when explicitly provided.

Changes:

• Modified core logic to detect and handle relative vs. absolute endpoint URLs
• Added a new playground environment (playground-relative) with comprehensive test coverage for the relative path feature
• Updated CI workflow to test both absolute and relative URL configurations

Reviewed changes

Copilot reviewed 11 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/astro-umami/src/index.ts	Core implementation: added isRelativePath() and buildScriptSrc() helpers; modified script generation logic to handle relative paths and conditionally set data-host-url
playground-relative/astro.config.ts	Configuration for relative path playground using /_umami endpoint
playground-relative/tests/relative-path.spec.ts	Comprehensive test suite verifying relative path behavior, script loading, and multi-domain scenarios
playground-relative/package.json	Dependencies and scripts for the relative path playground
playground-relative/playwright.config.ts	Playwright configuration for running tests on port 4322
playground-relative/src/pages/index.astro	Simple test page for the relative path playground
playground-relative/tsconfig.json	TypeScript configuration for the playground
playground-relative/.gitignore	Standard gitignore entries for Astro and Playwright artifacts
pnpm-workspace.yaml	Added playground-relative to workspace packages
package.json	Updated test script to include both playgrounds
.github/workflows/test.yml	Modified CI workflow to build package once and test both playground environments

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[Copilot]

Arrow function parameter should use parentheses around url for consistency with the project's style, especially since TypeScript benefits from explicit parameter typing.

Suggested change

	const scriptRequest = requests.find(url => url.includes("script.js"));
	const scriptRequest = requests.find((url) => url.includes("script.js"));