Nexidion 4.3.3 — Targeted editing and navigation fixes

This maintenance release adds safe, targeted content editing and fixes navigation,
version history, managed images, and summary workflows.

Targeted editing

New patch_node API: replace exact text without resending an entire node.
Expected versions and match counts prevent unintended changes; replacements
are atomic and respect existing permissions, write locks, and protected sources.
Preview changes with a dry-run diff. A changed patch creates exactly one new
version; dry-runs and unchanged patches leave content and history untouched.
The task runner uses the same patch service and records only saved changes.
Summary-only refreshes use set_summary without creating content versions.

Long version titles stay inside the sidebar, keeping the diff button visible.
Deep breadcrumb paths collapse into an ancestor menu; all links use the active
vault ID, fixing navigation to /vaults/undefined/....
Switching vaults clears stale selections and workspace state.
Managed images load correctly when revisiting cached content.
Copying AI summaries always includes node titles, UUIDs, and hierarchy.
Summary generation chooses a configured provider instead of an unavailable
local default; OpenRouter is supported in the provider selector.
The admin dashboard shows the running application version and database revision.

Nexidion MCP 1.4.0 exposes the new patch tool. Upgrade Nexidion before the
connector; earlier connector tools remain available.
No new database migration is introduced by 4.3.3.
Docker images are published as rhabermann/nexidion:v4.3.3 for Linux AMD64
and ARM64. The same image runs the application and task runner.

407 backend tests, 22 MCP tests, and 10 frontend tests passed. Frontend lint
and production build passed with existing warnings.