Prepare obsidian-test-session 0.3.0

[vrtmrz]

Prepare @vrtmrz/obsidian-test-session 0.3.0 so consumers can qualify exact Obsidian versions and discover standard Windows installations.

Changes

• Update the package manifest and matching lockfile entry from 0.2.6 to 0.3.0.
• Reconcile the package updates with the changes since the published 0.2.6 source, including the reviewed AppImage catalogue, runtime version policy, renderer fixes, and Windows executable discovery.
• Document migration for managed Linux discovery, exact reviewed AppImage versions, and the required PluginReadiness.obsidianVersion field. These public-contract changes warrant a minor release while the package is in 0.x.

Validation

• NODE_OPTIONS=--max-old-space-size=3072 VITEST_MAX_WORKERS=1 npm run verify:workspace: passed, including installed tarball-consumer checks.
• NODE_OPTIONS=--max-old-space-size=3072 VITEST_MAX_WORKERS=1 npm run test:e2e:obsidian:validated: all 10 scenarios passed with reviewed Obsidian 1.13.6 on Linux ARM64.
• Inspected the 0.3.0 tarball: compiled code and types, licence, package metadata, README, updates, and usage guide are present; tests and local fixtures are excluded.
• Current-candidate real-application validation covers Linux ARM64. Windows executable discovery has focused automated coverage and the contributor verification recorded in Discover official Windows Obsidian installs #55.

This PR prepares the release metadata. npm staging, publication, registry-consumer validation, and dist-tag promotion follow separately.