feat: v2.8.0 — Artifacts uploads and plugin links, console tab combos, account avatars

- Artifacts hub: upload a file from the computer; make a skill by uploading a
  Markdown file, files, a folder or a .zip/.skill, or by writing it in the
  dialog; add plugins by picking from the list a marketplace link answers
  (POST /api/artifacts/plugin/inspect); Settings → AI tools → Artifacts Hub.
- Console tabs are combos of up to four split panes (ConsoleTabs, PaneGrid).
- Accounts: an own avatar (PUT/DELETE /api/me/avatar, raster only, ≤ 1 MB,
  <data dir>/avatars/), shown with name and role at the sidebar's foot and on
  the workspace owner groups (GET /api/users/:id/avatar, owner_avatar_at).
- Users page: per-user storage (GET /api/users/storage, measured in a worker)
  and account-pool spend/tokens per account (server/lib/pool-usage.js).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/lib/claude-pool.js

@@ -15,9 +15,9 @@
  *   1. an account whose last quota reading is ≥ `BLOCK_PERCENT` in either
  *      window goes last (still used when every account is that full);
  *   2. fewest live panes (spreads concurrent sessions);
- *   3. least $ spent in the last 5 hours, then in the last 7 days — summed from
- *      `token_usage_hourly` for the sessions its runs (`dashboard_runs.account`)
- *      started.
+ *   3. least $ spent in the last 5 hours, then in the last 7 days — the
+ *      sessions its runs (`dashboard_runs.account`) held, over the hours they
+ *      held them (pool-usage.js).
  * The quota is read with the account's own token in the background, at most
  * every `QUOTA_TTL_MS`; a token the usage endpoint refuses simply has no
  * reading, and ranking falls back to spend.
@@ -375,47 +375,8 @@ function quotaPercent(name) {
 
 // ── What AgentHub recorded per account ─────────────────────────────────────
 
-const USAGE_COLS = [
-  "input_tokens",
-  "output_tokens",
-  "cache_read_tokens",
-  "cache_write_tokens",
-  "cache_write_1h_tokens",
-  "web_search_requests",
-  "web_fetch_requests",
-  "code_execution_requests",
-  "long_input_tokens",
-  "long_output_tokens",
-  "long_cache_read_tokens",
-  "long_cache_write_tokens",
-  "long_cache_write_1h_tokens",
-];
-
-/**
- * $ spent on `account` since `sinceHour` (`YYYY-MM-DDTHH`, UTC): the hourly
- * usage of every session one of its runs started, from that run's start hour.
- * ponytail: a session later resumed on ANOTHER account keeps counting here
- * too; split by run end time if that ever skews a ranking.
- */
-function spendSince(account, sinceHour) {
-  const { db, stmts } = require("../db");
-  const { calculateCost } = require("../routes/pricing");
-  const rows = db
-    .prepare(
-      `WITH s AS (
-         SELECT session_id, MIN(substr(started_at, 1, 13)) AS since
-           FROM dashboard_runs
-          WHERE tool = 'claude' AND account = ? AND session_id IS NOT NULL
-          GROUP BY session_id)
-       SELECT h.model, h.speed, h.inference_geo, h.service_tier,
-              ${USAGE_COLS.map((c) => `SUM(h.${c}) AS ${c}`).join(", ")}
-         FROM s JOIN token_usage_hourly h
-           ON h.session_id = s.session_id AND h.hour >= s.since AND h.hour >= ?
-        GROUP BY h.model, h.speed, h.inference_geo, h.service_tier`
-    )
-    .all(account, sinceHour);
-  return rows.length ? calculateCost(rows, stmts.listPricing.all()).total_cost : 0;
-}
+/** $ and tokens of the last 5 h / 7 d (pool-usage.js). */
+const usageOf = (account) => require("./pool-usage").accountUsage("claude", account);
 
 function livePanes(account) {
   const { db } = require("../db");
@@ -426,8 +387,6 @@ function livePanes(account) {
     .get(account).n;
 }
 
-const hourAgo = (hours) => new Date(Date.now() - hours * 3600e3).toISOString().slice(0, 13);
-
 /** Every account with what the balancer sees — never a token. */
 function poolStatus() {
   return allAccounts().map((a) => {
@@ -442,8 +401,7 @@ function poolStatus() {
       expiresAt: expiresAt(a),
       expired: expired(a),
       livePanes: livePanes(a.name),
-      spend5h: spendSince(a.name, hourAgo(5)),
-      spend7d: spendSince(a.name, hourAgo(24 * 7)),
+      ...usageOf(a.name),
       quota: q
         ? {
             fiveHour: q.fiveHour || null,
@@ -481,8 +439,11 @@ function pick(member) {
   let usable = allAccounts().filter((a) => !expired(a));
   if (usable.length === 0) return null;
   if (!member) {
-    // A host pane's home holds the host's own login.
-    usable = usable.filter((a) => a.kind === "token");
+    // A host pane's home holds the host's own login — a pool account only when
+    // it was moved in from there (`hostHolds`) and is still the pair on disk:
+    // the pane then runs on it as it is, and its usage is that account's.
+    const disk = homeCreds(HOST_ACCT);
+    usable = usable.filter((a) => a.kind === "token" || ownsHome(a, HOST, disk));
   } else {
     const disk = homeCreds(member);
     const placed = disk && usable.find((a) => ownsHome(a, member.name, disk));
@@ -501,13 +462,14 @@ function pick(member) {
   const ranked = usable
     .map((a) => {
       const percent = quotaPercent(a.name);
+      const u = usageOf(a.name);
       return {
         a,
         key: [
           percent != null && percent >= BLOCK_PERCENT ? 1 : 0,
           livePanes(a.name),
-          spendSince(a.name, hourAgo(5)),
-          spendSince(a.name, hourAgo(24 * 7)),
+          u.spend5h,
+          u.spend7d,
         ],
       };
     })
@@ -524,7 +486,8 @@ function pick(member) {
  * The account a new Claude pane should run on — `{name, kind, token?}` — or
  * null when the pool has nothing this pane may use. Synchronous (a spawn
  * cannot wait on the network): it ranks on the cached quota and starts a
- * background re-read. A `login` is only ever offered for a member.
+ * background re-read. A `login` is offered for a member, and for a host pane
+ * only when it is the host's own login (`hostHolds`), which stays as it is.
  */
 function pickAccount(member = null) {
   const a = pick(member);
@@ -545,6 +508,8 @@ function forSpawn(member = null) {
   if (a.kind === "token") {
     return { name: a.name, env: { CLAUDE_CODE_OAUTH_TOKEN: a.token }, place: () => {} };
   }
+  // The host's own login is already in place; the server keeps it fresh.
+  if (!member) return { name: a.name, env: {}, place: () => {} };
   return {
     name: a.name,
     env: {},