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.

docs/LANES.md

@@ -407,7 +407,7 @@ The dashboard web UI merges workspaces and runs into a single **Workspace** page
   Keyboard: the terminal keeps Tab and Shift+Tab (`claude` cycles its permission mode on Shift+Tab), so **Ctrl+M** toggles *Tab moves focus* — VS Code's way out of its terminal — and Tab then leaves the pane; **Cmd+F** (macOS) / **Ctrl+Shift+F** opens a find bar. URLs open in a new tab; a selection tmux copies (OSC 52) lands in the browser clipboard, and that path is write-only — nothing in the pane can read your clipboard. `agenthub.terminal.screenReader` = `"1"` in `localStorage` turns on xterm's screen-reader mode. While the socket is down a **Reconnecting…** overlay says keystrokes are not reaching the pane; it re-attaches by itself. In the session view, outside a terminal or a text field, `Alt+1`–`Alt+4` focuses pane 1–4, `Alt+\` splits the focused pane right with a new terminal, and `Alt+W` closes the focused pane (its session stays a tab).
 - **Clipboard in a pane** — the workspace's tmux session is started with the graphical session's own `DISPLAY`/`WAYLAND_DISPLAY`/`XAUTHORITY`/`XDG_RUNTIME_DIR` (read from `systemctl --user show-environment`, this process's own values winning; `server/lib/desktop-env.js`). The dashboard normally runs as a systemd *user* service, which has none of them, so a pane it started had no clipboard at all and `claude` answered "no image found in clipboard" on every image paste while the same CLI pasted fine in a terminal. Only those four names are forwarded, and only into panes this dashboard spawns — an already-running pane keeps the environment it was started with, so it needs a restart to gain one.
 - **Scrollbar in a pane** — every pane gets tmux's `mouse on` and `pane-scrollbars on` with a visible style (`pane-scrollbars-style fg=brightwhite,bg=black,width=1`, `enableMouse` in `server/lib/tmux.js`; tmux 3.7+ — one column, since tmux 3.7c reserves `width` columns but paints only the first and a wider bar left a column of stale cells that read as a second scrollbar). tmux keeps no history and draws no scrollbar on the alternate screen, so a `claude` pane under `"tui": "fullscreen"` (`~/.claude/settings.json`) scrolls inside Claude's own UI instead. AgentHub no longer forces it inline (`CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN=1`): inline, every time the pane narrowed tmux re-wrapped Claude's full-width rules and pushed lines into history that its redraw could not clear, duplicating the banner and transcript. A pane started before this change keeps inline mode until it is restarted. Every pane's CLI (and a Terminal tab's shell) also starts only once a client is attached — 2 s at most — so nothing is drawn at tmux's 80×24 birth size and re-wrapped on the attach (`WAIT_FOR_CLIENT` in `server/lib/pty-run.js`, issue #55).
-- **Tabs** — the session view's console is a tab bar (`client/src/components/run/ConsoleTabs.tsx`) over the workspace's live tmux sessions — at most ten, its slots 0–9: slot 0 is the workspace's `agenthub-lane-<id>` (its `run_id`), slots 1–9 are `agenthub-lane-<id>-<slot>`. Every tab is a **combo**: a group of one to four split panes, each session in exactly one tab (`PaneGroups` in `client/src/lib/paneLayout.ts`). A one-pane tab shows its AI tool's icon and name (or **Terminal**); a combo tab shows every pane's icon and name, and the most urgent state dot. The active tab is the one on screen and its focused pane is the URL's `?run=`, so the Changes panel and Analyst follow it. A click shows a tab; **Ctrl/Cmd+click** on a one-pane tab or a `+` item brings it into the tab on screen, split to the right (a full tab — four panes — opens it as a tab of its own instead), and a one-pane tab dragged onto a pane joins that tab there. Any tab drags along the bar to reorder it; a pane's header dragged onto the bar takes that pane out into a tab of its own at that place. Every live session stays mounted and those of other tabs are hidden with CSS, so switching tabs never drops a terminal. A tab's **×** stops every session in it (`DELETE /api/run/<runId>`, after a confirm when one is an AI tool); with no tab left it moves to the home. The **+** menu opens a new tab in the first free slot, which the server picks (`slot: "auto"`, under the workspace lock): **New terminal** (your own default shell in the workspace folder — `POST /api/lanes/:id/start {slot, shell: true}`, recorded as tool `shell`; it is not an agent, so the workspace's `run_id`/`status` are left alone), each installed, enabled AI tool (started bare, on its default model, no prompt), and **Agent settings…** (Settings → Agents). With ten sessions open **+** is disabled. EVERY tab is bound to the sidebar's selection. A tab has no header of its own (no title, no **Active runs** list, no **New run**): other sessions are opened from the sidebar or the home's Recents. (The old fixed 1/2/4 split layout and its `agenthub.workspace.splitView` key are gone; **Split panes** replaces them.)
+- **Tabs** — the session view's console is a tab bar (`client/src/components/run/ConsoleTabs.tsx`) over the workspace's live tmux sessions — at most ten, its slots 0–9: slot 0 is the workspace's `agenthub-lane-<id>` (its `run_id`), slots 1–9 are `agenthub-lane-<id>-<slot>`. Every tab is a **combo**: a group of one to four split panes, each session in exactly one tab (`PaneGroups` in `client/src/lib/paneLayout.ts`). A one-pane tab shows its AI tool's icon and name (or **Terminal**); a combo tab shows every pane's icon and name, and the most urgent state dot. The active tab is the one on screen and its focused pane is the URL's `?run=`, so the Changes panel and Analyst follow it. A click shows a tab; **Ctrl/Cmd+click** on a one-pane tab or a `+` item brings it into the tab on screen, split to the right (a full tab — four panes — opens it as a tab of its own instead), and a one-pane tab dragged onto a pane joins that tab there. Any tab drags along the bar to reorder it; a pane's header dragged onto the bar takes that pane out into a tab of its own at that place. Dropped on the MIDDLE of another tab (it highlights), a tab — or a pane's header — joins that tab instead, in a fixed order: the second pane goes to the right (left | right), the third under the right pane, the fourth under the left pane (2×2); a drop that would pass four panes reorders instead (`joinGroup`). Every live session stays mounted and those of other tabs are hidden with CSS, so switching tabs never drops a terminal. A tab's **×** stops every session in it (`DELETE /api/run/<runId>`, after a confirm when one is an AI tool); with no tab left it moves to the home. The **+** menu opens a new tab in the first free slot, which the server picks (`slot: "auto"`, under the workspace lock): **New terminal** (your own default shell in the workspace folder — `POST /api/lanes/:id/start {slot, shell: true}`, recorded as tool `shell`; it is not an agent, so the workspace's `run_id`/`status` are left alone), each installed, enabled AI tool (started bare, on its default model, no prompt), and **Agent settings…** (Settings → Agents). With ten sessions open **+** is disabled. EVERY tab is bound to the sidebar's selection. A tab has no header of its own (no title, no **Active runs** list, no **New run**): other sessions are opened from the sidebar or the home's Recents. (The old fixed 1/2/4 split layout and its `agenthub.workspace.splitView` key are gone; **Split panes** replaces them.)
 
 - **Split panes** — the console splits like VS Code (`client/src/components/run/PaneGrid.tsx`, model in `client/src/lib/paneLayout.ts`): one binary tree of splits PER TAB, each side by side or stacked at a ratio, whose leaves are the workspace's slots — at most four panes in a tab, a session never shown twice. **Ctrl/Cmd+click** a one-pane tab, a `+` item or a sidebar session row brings it into the tab on screen, to the right of the focused pane (the intent rides on the navigation's state, never in the URL); with more than one pane each gets a slim header: **drag** it (or a tab) onto another pane — its edge splits there, its middle swaps the two —, its **▾** shows another live session in it (swapping with the pane that showed it), **Split right / Split down** puts a not-shown session or a **New terminal** beside it, and **×** takes the pane out of this tab into a tab of its own (its session keeps running). A session dropped or swapped in from another tab leaves that tab. Dividers drag (or move by arrow keys) between 10% and 90%. Clicking in (or tabbing into) a pane focuses it, `?run=` follows — so the right panel, Analyst and the sidebar read the focused session — and the keyboard goes with it: only the focused pane's terminal takes it when it appears. A pane closes when its terminal reports that its session ended (exited, closed from another browser); the run list itself only prunes a remembered layout on a workspace's first read, and a pane opened here whose session never got listed — one empty read, which the server returns on any tmux error, never wipes a split. A session ending while the home or a replay is shown only closes its pane; the URL stays. The tabs and their layouts are a viewer preference kept per workspace in `localStorage` (`agenthub.workspace.paneLayout`, `{groups, active}`; a stored pre-tab single layout reads as one tab), never on the server. Every pane is an absolutely placed sibling keyed by its slot, so splitting, swapping or resizing never re-parents — and so never remounts — a live terminal; the session view itself fills the page edge to edge, its tab bar and the right panel's activity bar one header strip.
 - **Workspace grid** — one card per workspace, 1 column, 2 at `md`, 3 at `xl`. Each card carries the workspace id, liveness dot and status, title, declared stage and time-on-stage, the `auto:` chip when detection leads, the kind and CI tags, the working-copy facts from `GET /api/lanes/:id/git`, and the action row. The needs-you message (`needs_action`) is on the workspace list tile only — the detail card no longer repeats it as a banner.