security(web): avoid arbitrary vault-path writes from Obsidian dashboard flows

[jerry609]

Parent Epic

#159 — [Epic] Obsidian CLI 集成 — 研究知识管理

Problem

A naive dashboard implementation would let the web backend accept an arbitrary vault_path and write markdown files directly to that path. In deployed environments this becomes a remote arbitrary filesystem write surface.

Decision

Keep the Web dashboard transport local-first:

• web UI may generate/copy local CLI commands
• web UI may download export artifacts
• direct vault writes from browser-triggered server routes require a separate trusted local bridge / allowlisted directory model

Acceptance Criteria

• Document why hosted web routes must not write arbitrary vault paths
• Keep current web implementation on CLI handoff / safe download path only
• Track any future local-agent or allowlisted-dir transport as a separate design