refactor: rename diigo-dump to diigo-cache

Pure rename ahead of the dump worker's evolution into a bookmark cache
(goal 1c), so history follows the files. The diigo-login helper script
is dropped: the cookie now enters through webapp's mint form, never a
local script.

diigo-dump/scripts/diigo-login

@@ -1,56 +0,0 @@
-#!/bin/sh
-# diigo-login: OBSOLETE but kept for terminals: superseded by the /_connect
-# page flow (paste the cookie in the browser form; no clipboard/askpass).
-# Prompt for the diigo.com session cookie via SSH_ASKPASS, verify it
-# against the interact_api (one page), mint the webapp instance via the
-# running dev server, and write the instance id to stdout (for
-# `>> .dev.vars`). The cookie itself lives only in the DO's storage —
-# never on disk, never in logs.
-#
-# usage: pnpm -s diigo-login >> .dev.vars   (dev server must be up; needs
-#        a display for the GUI prompt)
-set -eu
-
-: "${SSH_ASKPASS:=/usr/bin/ssh-askpass}"
-export SSH_ASKPASS
-
-# the prompt text (SSH_ASKPASS_PROMPT is what ksshaskpass/gnome-askpass read)
-export SSH_ASKPASS_PROMPT="diigo.com login: paste the Cookie header from devtools"
-
-cookie=$(DISPLAY="${DISPLAY:-:0}" "$SSH_ASKPASS" 2>/dev/null) || {
-	echo "$0: askpass failed (need a display; or export SSH_ASKPASS yourself)" >&2
-	exit 1
-}
-[ -n "$cookie" ] || {
-	echo "$0: empty cookie" >&2
-	exit 1
-}
-
-# verify before committing anything: the endpoint the worker will use,
-# with the same headers WebApp will send
-target='https://www.diigo.com/interact_api/load_user_items?sort=updated&count=1&page_num=1'
-status=$(curl -s -o /dev/null -w '%{http_code}' \
-	-H "cookie: $cookie" \
-	-H 'user-agent: Mozilla/5.0 (X11; Linux x86_64) Gecko/20100101 Firefox/141.0' \
-	-H 'x-requested-with: XMLHttpRequest' \
-	"$target")
-[ "$status" = 200 ] || {
-	echo "$0: diigo said $status for that cookie; not writing .dev.vars" >&2
-	exit 1
-}
-
-# mint the webapp instance (persist id: the instance keeps the cookie, so
-# re-running this mint only replaces an *invalid* cookie). /_mint speaks
-# the browser form protocol: proxyMint is html, not json.
-minted=$(curl -s -D /tmp/opencode/diigo-mint-headers -X POST http://localhost:8787/_mint \
-	--data-urlencode "cookie=$cookie") || {
-	echo "$0: could not reach the dev server at :8787 (is it up?)" >&2
-	exit 1
-}
-webapp_id=$(grep -i '^x-diigo-web-id:' /tmp/opencode/diigo-mint-headers | tr -d '\r' | awk '{print $2}')
-[ -n "$webapp_id" ] || {
-	echo "$0: mint failed; server said: $(printf '%s' "$minted" | tr -d '\n' | head -c 200)" >&2
-	exit 1
-}
-
-printf 'DIIGO_WEB_ID="%s"\n' "$webapp_id"