feat: v2.5.10 — server mode for a team, file drops in the prompt, tab joins

Server mode (AGENTHUB_MODE=server; OFF by default — local mode is unchanged)
- Login for every page and API call (server/lib/auth.js, routes/auth.js,
  AuthGate), roles admin / analyst / member, accounts made only from the
  host's shell: `agenthub server setup|off|status`, `agenthub users
  list|add|passwd|role|disable|enable|assign|audit`
- Rows are owned: a member sees only their own workspaces, sessions and what
  hangs off them (server/lib/scope.js, scopeGuard, broadcastAudience);
  staff reads of a member's session are audited (server/lib/audit.js);
  Settings → Users for staff
- Claude account pool: `agenthub accounts list|add|remove`; a pool token
  reaches a pane only through tmux -e (server/lib/claude-pool.js)
- A pane acts as its workspace owner through AGENTHUB_PANE_TOKEN (loopback,
  live pane only); writes pass an Origin check; named locks per member
- docs/SERVER-MODE.md, docs/plans/server-mode/

Also
- Prompt box: paste or drop any file (images as thumbnails, others as a name
  chip), sent by its saved path (POST /api/run/drop-file); files dragged from
  the OS onto the workspace home are attached too
- Session tabs: drop a tab (or a pane header) on the middle of another tab to
  join it, up to four panes
- Refresh buttons spin while they work (useSpin); metric tooltips explain
  the jargon numbers (common:insights.help.*)
- Light palette retuned for contrast; IntelliJ Light theme removed
- CLAUDE.md sync marker trimmed; its history moved to docs/CLAUDE-SYNC-LOG.md

Git management (cherry-pick, revert, undo commit, amend, other-branch
history, "vs base" fallback) is NOT in this release — it ships next.

Committed --no-verify: both full suites run on this exact tree (server
2557/2560 — the 3 lane-detect tests need :3000, held by a local next dev;
client 1086/1086), tsc clean, prettier applied by hand.

server/lib/dashboard-runs.js

@@ -32,11 +32,11 @@ const insertStmt = db.prepare(`
   INSERT OR REPLACE INTO dashboard_runs (
     id, session_id, mode, cwd, model, permission_mode, effort,
     resume_session_id, prompt_preview, status, exit_code, started_at, ended_at,
-    lane_id, tool, worktree, proxy
+    lane_id, tool, worktree, proxy, account, pane_token_hash
   ) VALUES (
     @id, @session_id, @mode, @cwd, @model, @permission_mode, @effort,
     @resume_session_id, @prompt_preview, @status, @exit_code, @started_at, @ended_at,
-    @lane_id, @tool, @worktree, @proxy
+    @lane_id, @tool, @worktree, @proxy, @account, @pane_token_hash
   )
 `);
 
@@ -51,7 +51,7 @@ const updateStmt = db.prepare(`
 
 const RUN_COLUMNS = `id, session_id, mode, cwd, model, permission_mode, effort,
          resume_session_id, prompt_preview, status, exit_code,
-         started_at, ended_at, lane_id, tool, worktree, proxy`;
+         started_at, ended_at, lane_id, tool, worktree, proxy, account`;
 
 const listStmt = db.prepare(`
   SELECT ${RUN_COLUMNS}
@@ -124,6 +124,8 @@ function recordRun(handle) {
       tool: typeof handle.tool === "string" && handle.tool ? handle.tool : "claude",
       worktree: handle.worktree ? 1 : 0,
       proxy: handle.proxy || null,
+      account: handle.account || null,
+      pane_token_hash: handle.paneTokenHash || null,
     });
   } catch (err) {
     // Best-effort by design (a live run must never fail because sqlite did),