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/nslookup.md

@@ -0,0 +1,19 @@
+# nslookup
+> DNS query tool for testing name resolution
+
+**Category:** [[categories/network-analysis|network-analysis]] | **Tier:** Rich (FOR610)
+
+## Usage
+```bash
+nslookup domain.com
+```
+
+## Related Tools
+- [[tools/iptables|iptables]] — Linux firewall and NAT tool for redirecting IP-based malware
+- [[tools/torsocks|torsocks]] — Route network traffic through the Tor anonymity network
+
+## FOR610
+**Labs:** 1.3
+**Sections:** 1
+
+#dns #testing