Add markdown wiki with 473 pages and zk browser

Generate interlinked wiki from master inventory: 397 tool pages,
15 workflow pages, 27 recipe pages, 33 category pages, plus index.
All pages use [[wiki-links]] for cross-navigation between tools,
workflows, recipes, and categories (1782 links total).

Install zk for interactive browsing with fzf search, tag filtering,
and backlink discovery. Add 'fhelp wiki' command and Makefile target.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

data/generated/wiki/tools/feh.md

@@ -0,0 +1,26 @@
+# feh
+> Lightweight image viewer for viewing extracted images from documents
+
+**Category:** [[categories/view-or-edit-files|View or Edit Files]] | **Tier:** Rich (FOR610)
+**Docs:** [https://docs.remnux.org/discover-the-tools/view+or+edit+files](https://docs.remnux.org/discover-the-tools/view+or+edit+files)
+
+## Usage
+```bash
+feh extracted_image.jpg
+```
+
+## Recipes
+- [[recipes/pdf-object-extraction|Extract Embedded Object from PDF]]
+
+## Related Tools
+- [[tools/dos2unix|dos2unix]] — Convert text files with Windows or macOS line breaks to Unix
+- [[tools/evince|evince]] — View documents in a variety of formats, including PDF.
+- [[tools/imagemagick|imagemagick]] — View and manipulate image and related files.
+- [[tools/scite|scite]] — Edit text files.
+- [[tools/vbindiff|vbindiff]] — Compare binary files.
+
+## FOR610
+**Labs:** 3.1
+**Sections:** 3
+
+#image-viewer