Add /review-submittal slash command

Wires the slash command referenced in the submittal-review skill's
SKILL.md so PMs can invoke it directly as /review-submittal <path>
instead of relying on natural-language triggering.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

plugins/willow-pmtools/commands/review-submittal.md

@@ -0,0 +1,17 @@
+---
+description: Pre-architect review of a construction submittal (PDF or folder). Optional --spec flag points at a project spec book for paragraph-level citations.
+argument-hint: "<pdf or folder path> [--spec <spec book path>]"
+---
+
+Invoke the `willowbrook-submittal-review` skill on the path supplied in `$ARGUMENTS`.
+
+Steps:
+
+1. Parse `$ARGUMENTS`:
+   - First positional arg → submittal path (PDF or folder)
+   - Optional `--spec <path>` → project spec book path
+   - If no path is supplied, ask the PM for one and stop.
+2. Load the skill at `skills/willowbrook-submittal-review/SKILL.md` and follow its workflow verbatim, including the hard rules (every "pass" must cite a spec paragraph; 0.95 confidence floor; directive tone; DRAFT-only — never send/post/upload anything).
+3. Produce the on-screen memo, the `review/submittal_<num>_review.json`, and the `.docx` checklist as specified in SKILL.md.
+
+Do not skip steps. Do not invent spec citations. If the spec book isn't supplied or the section isn't found, the max status is `Approved as Noted`.