Point the shipped agent skills at omacom/omarchy (#10532)

The repository moved from basecamp/omarchy to omacom/omarchy, but the skills
Omarchy installs into ~/.claude/skills, ~/.codex/skills and ~/.agents/skills
still name the old owner. Most gh calls follow the rename, so nothing looks
wrong in normal use. Search does not: `gh issue list --repo basecamp/omarchy
--search ...` exits 0 with no output, and the raw search API answers
"Validation Failed". An agent following contributing.md or reporting.md runs
its duplicate check before filing, sees zero matches, and files a duplicate.

Replace the owner in contributing.md, reporting.md and the issue-template
contact link, which is the same stale name on the contributor path. The git
clone and release URLs in bin/ and manual/ are left alone: GitHub redirects
those, and channel-test.sh asserts the exact clone URL, so changing them is a
separate change.

Fixes #10118

Written by Claude Fable 5.1 via Claude Code, reviewed by Marc Morriss

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

.github/ISSUE_TEMPLATE/config.yml

@@ -1,7 +1,7 @@
 blank_issues_enabled: false
 contact_links:
   - name: Suggestion
-    url: https://github.com/basecamp/omarchy/discussions/categories/suggestions
+    url: https://github.com/omacom/omarchy/discussions/categories/suggestions
     about: Suggest a new feature, change to existing feature, or other ideas in Discussions.
   - name: Support
     url: https://omarchy.org/discord