Projects editor: scan a folder to bulk-import agent-ready projects

[dpetreleyai]

Problem

Adding many existing project folders means one editor row at a time with a browse dialog each. For a workspace that already has dozens of agent-ready folders (each carrying a CLAUDE.md/AGENTS.md), initial setup is pure manual data entry.

Intended fix

A "Scan folder…" button in the Projects editor:

• native folder picker, then a Rust command walks the chosen root (max 2 levels deep, skipping node_modules/.git/target/… like scan_html does) and returns every directory containing a CLAUDE.md or AGENTS.md (case-insensitive);
• hits not already present (by path) are appended as editable rows — label = folder name, group = immediate parent folder when the hit is nested (pairs with Sidebar: optional collapsible project groups #43), nothing saved until the user hits Save;
• a status line reports found/added/skipped counts.

Read-only scan, additive rows only, i18n EN/NL.

[astetic-dev]

Acknowledged - deliberately not part of 0.4.0. Still under consideration for a future release; keeping it open on the backlog.