Release v0.3.0

[czpython]

Prepares the v0.3.0 release: version bump, lockfile, and the changelog section.

Highlights

• Logged-in browser sessions. An extension declares a browser session for a site; the operator logs in once through a Druks-hosted browser window, and a workflow borrows that authenticated, encrypted login across runs.
• Installed apps mount in the shell. An app ships an ESM entry and declared navigation, and Druks renders it inside the dashboard — borrowing the shell's components, markdown renderer, form fields, and gates.
• One OAuth engine. OauthClient in druks.services runs every OAuth exchange, with the MCP client rewired onto it.
• Usage is a platform surface, not an app you install.

The full set of Added / Changed / Fixed entries is in CHANGELOG.md.

Contents

• pyproject.toml — version 0.2.0 → 0.3.0
• uv.lock — relocked (only the druks version moved)
• CHANGELOG.md — new [0.3.0] section, covering the 42 commits since v0.2.0

The annotated tag and GitHub release follow the merge, per docs/releasing.md.