feat: add !paste command and unit tests for 5 core plugins

Add cmd_paste to flaskpaste plugin (create paste, return URL).
Add test suites for encode, hash, defang, cidr, and dns plugins
(83 new test cases, 1093 total).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ROADMAP.md

@@ -116,8 +116,8 @@
 - [ ] URL shortener integration (shorten URLs in alerts and long output)
 - [ ] Webhook listener (HTTP endpoint for push events to channels)
 - [ ] Granular ACLs (per-command permission tiers: trusted, operator, admin)
-- [ ] `paste` plugin (manual paste to FlaskPaste)
-- [ ] `shorten` plugin (manual URL shortening)
+- [x] `paste` command (manual paste to FlaskPaste)
+- [x] `shorten` command (manual URL shortening)
 - [x] `emailcheck` plugin (SMTP VRFY/RCPT TO)
 - [x] `canary` plugin (canary token generator/tracker)
 - [x] `virustotal` plugin (hash/URL/IP/domain lookup, free API)
@@ -126,5 +126,5 @@
 - [x] `mac` plugin (OUI vendor lookup, local IEEE database)
 - [x] `pastemoni` plugin (monitor paste sites for keywords)
 - [ ] `cron` plugin (scheduled bot commands on a timer)
-- [ ] Plugin command unit tests (encode, hash, dns, cidr, defang)
+- [x] Plugin command unit tests (encode, hash, dns, cidr, defang)
 - [ ] CI pipeline