feat(hooks+skills): destructive-bash confirm + architecture suite + problem-solving routing

Three improvements bundled together:

1. New hook — `destructive-bash-confirm.py` (PreToolUse/Bash):
   Gates `git push --force`, `git reset --hard`, `git clean -f`,
   `git branch -D`, and `rm -rf` behind a confirmation modal with the
   command, local context (branch, uncommitted counts, targeted paths),
   and a severity banner. Elevates severity when force-pushing protected
   branches (main/master/develop/release/prod) or when rm -rf targets
   root, home, or wildcard paths. Reuses _common.py.

2. Architecture suite rename — the "Part of the arch-* suite" footer in
   arch-design, arch-decide, arch-document, arch-evaluate descriptions
   now reads "Part of the architecture suite (arch-design / arch-decide
   / arch-document / arch-evaluate + c4-analyze / c4-diagram for
   notation-specific diagramming)." Matching footers added to c4-analyze
   and c4-diagram. c4-* keep their framework-specific prefix (C4 is a
   notation, arch-* is framework-agnostic workflow) but are now
   discoverable as suite members.

3. Problem-solving cluster routing — added YAML frontmatter with
   descriptions (including "Do NOT use for X (use Y)" clauses) to
   debug/SKILL.md and fix-issue/SKILL.md. Previously both had no
   frontmatter at all, which broke skill-router discovery. The four
   cluster members (debug, fix-issue, root-cause-trace, five-whys) now
   route unambiguously by description alone.

1 files changed, 5 insertions, 0 deletions

diff --git a/debug/SKILL.md b/debug/SKILL.md
index 7f3771a..7b207aa 100644
--- a/debug/SKILL.md
+++ b/debug/SKILL.md
@@ -1,3 +1,8 @@
+---
+name: debug
+description: Investigate a bug or test failure methodically through four phases — understand the symptom (reproduce, read logs, locate failure point, trace data flow), isolate variables (minimal repro, bisect), form and test hypotheses, then fix at the root. Captures evidence before proposing fixes; rejects shotgun debugging; escalates to architectural investigation after three failed fix attempts. Use when the failure mode is unclear, the failure reproduces inconsistently, or you're about to start guessing. Do NOT use for clear local bugs where the fix site is obvious (just fix it), for ticket-driven implementation work with a known fix (use fix-issue), for backward-walking a specific error up the call stack (use root-cause-trace), or for process/organizational root-cause analysis of recurring incidents (use five-whys). Companion to fix-issue / root-cause-trace / five-whys — debug is the broad investigative workflow; the others specialize.
+---
+
 # /debug — Systematic Debugging
 
 Investigate a bug or test failure methodically. No guessing, no shotgun fixes.