dsh-obsidian-agent-wiki: Searchable SQLite Obsidian Memory for DeepSeek Harness

`dsh-obsidian-agent-wiki` is a DeepSeek Harness plugin designed to provide agents with a local knowledge base access layer featuring full-text search and structured filtering. Built on Node 22's built-in SQLite, it builds an index on startup, supports filtering by path, tags, and other criteria, and provides tools such as `wiki_read`, `wiki_write`, and `wiki_search`. Installation requires dsh ≥ 0.1.1-rc.2; after configuring it to point to an Obsidian vault, it is ready to use.