fix: prevent "document is not defined" error in non-DOM environments

[ZayanKhan-12]

Description

Constructing MetaMaskInpageProvider with shouldSendMetadata enabled throws a document is not defined ReferenceError in non-DOM environments (e.g. Chrome extension background scripts / service workers), because the constructor unconditionally reads document.readyState and registers a DOMContentLoaded listener on window.

This PR guards the DOM access:

• MetaMaskInpageProvider: if typeof document === 'undefined', the missing document is treated as "already loaded" and the site metadata is sent immediately, instead of reading document.readyState / waiting for DOMContentLoaded.
• siteMetadata.ts: the site name/icon extraction now receives globalThis and falls back to location.hostname (and a null icon) when no document is available, so the metadata request no longer fails with an unhandled ReferenceError logged as an error. Also fixes a small inconsistency where getSiteName read the global window instead of its windowObject parameter for the hostname fallback.

Behavior in normal window contexts is unchanged.

Fixes #191

Testing

• yarn jest — all 9 suites / 135 tests pass, including new tests:
  • constructor sends site metadata immediately when the document has already loaded
  • constructor waits for DOMContentLoaded when the document is still loading
  • constructor does not throw and sends metadata immediately when document is undefined (simulated by mocking the document getter in jsdom)
  • sendSiteMetadata sends DOM-derived metadata, and falls back to the hostname when document is undefined
• yarn lint:eslint — passes (the two touched test files were added to the existing mixed-environment no-restricted-globals override, following the pattern used for EIP6963.test.ts et al.)
• yarn lint:misc --check — passes
• yarn build — passes

🤖 Generated with Claude Code

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Note

Low Risk
Small defensive guards on optional metadata sending; normal in-page behavior is preserved and covered by new tests.

Overview
Fixes document is not defined when MetaMaskInpageProvider is created with shouldSendMetadata in environments without a DOM (extension backgrounds, service workers).

The constructor now treats a missing document like a fully loaded page and calls sendSiteMetadata immediately instead of reading document.readyState or waiting on DOMContentLoaded. siteMetadata extraction uses globalThis and, when document is absent, falls back to location.hostname and a null icon (and uses the passed object for the hostname fallback instead of the global window).

Browser behavior is unchanged; tests cover DOM, loading, and no-document paths.

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