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/recipes/email-attachment-extraction.md

@@ -0,0 +1,18 @@
+# Extract and Triage Email Attachments
+> Pull attachments from an email and identify their types
+
+**Tools:** [[tools/emldump-py|emldump-py]], [[tools/file|file]], [[tools/sha256sum|sha256sum]]
+
+## Commands
+```bash
+# List email structure
+emldump.py <email.eml>
+# Extract all attachments
+emldump.py <email.eml> -d
+# Identify file types
+file attachment_*
+# Compute hashes for lookup
+sha256sum attachment_*
+```
+
+#recipe #emldump-py #file #sha256sum