docs(readme): move details into docs

[tkkhq]

Summary

Condenses README to quickstart, contributing, and license; moves installation, authentication, and project configuration details into docs/.

[Copilot]

Pull request overview

This PR streamlines the top-level README.md down to a quickstart, contributing, and license overview, relocating the more detailed installation, authentication, and project-configuration material into dedicated files under docs/. It also converts bare-filename mentions (e.g., CONTRIBUTING.md, LICENSE) into Markdown links. This improves README readability while keeping the detailed reference documentation discoverable via links.

Changes:

• Removed the npm postinstall, Authentication, and Project configuration sections from README.md, replacing them with a "More detail lives in docs/" link list.
• Added three new docs (installation.md, authentication.md, project-configuration.md) containing the relocated content, lightly reformatted into bullet lists.
• Converted plain filename references in the README into proper Markdown links.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
README.md	Condenses content, links out to new docs, and converts filename mentions into Markdown links.
docs/installation.md	New doc holding relocated installation and npm-wrapper details.
docs/authentication.md	New doc holding relocated signup/login/logout and environment-targeting guidance.
docs/project-configuration.md	New doc holding relocated volcano-config.yaml manifest and reconciliation semantics.

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[swkeever]

Clean, faithful move overall — the split reads well and the quickstart is more correct now that it uses the installed volcano binary. One content-parity note left inline; not a blocker.