chore(scripts): add test-personal-wiki.sh + NUWIKI_DEV_NO_SEED

test-personal-wiki.sh wraps start-vim.sh to open the user's real wiki
at ~/.vimwiki/personal_wiki (override with NUWIKI_PERSONAL_WIKI) — used
when reproducing user-reported bugs against actual content instead of
the seeded smoke-test wiki.

Also adds a NUWIKI_DEV_NO_SEED env var to start-vim.sh so seed_wiki
doesn't drop a scratch Notes.wiki into the user's real notes when we
point WIKI_DIR at an already-populated wiki.

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

start-vim.sh

@@ -12,6 +12,7 @@
 #   ./start-vim.sh path/to/note.wiki      # open a specific file
 #   NUWIKI_DEV_WIKI=/tmp/foo ./start-vim.sh
 #   NUWIKI_DEV_NO_LSP=1 ./start-vim.sh        # skip vim-lsp setup
+#   NUWIKI_DEV_NO_SEED=1 ./start-vim.sh       # use WIKI_DIR as-is (no scratch seeding)
 #   NUWIKI_DEV_SKIP_BUILD=1 ./start-vim.sh    # reuse the cached binary
 #
 # The release binary is rebuilt on every launch so source changes
@@ -77,6 +78,10 @@ ensure_vim_lsp() {
 }
 
 seed_wiki() {
+  if [[ "${NUWIKI_DEV_NO_SEED:-0}" == "1" ]]; then
+    log "NUWIKI_DEV_NO_SEED=1 — skipping wiki seed (using $WIKI_DIR as-is)"
+    return
+  fi
   mkdir -p "$WIKI_DIR" "$WIKI_DIR/diary"
   if [[ ! -f "$WIKI_DIR/index.wiki" ]]; then
     cat > "$WIKI_DIR/index.wiki" <<'EOF'