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.

client/src/components/run/TerminalView.tsx

@@ -14,9 +14,10 @@
  * (`loadXterm`), not bundled with the Workspace chunk.
  * Always painted dark, in the palette of the user's chosen DARK theme
  * (`lib/terminalTheme.ts`), recoloured live without re-attaching.
- * An image dropped on it is saved on the server (`POST /api/run/drop-image`)
- * and its PATH pasted into the pane — what a local terminal does on a drop,
- * and how `claude` attaches an image. The pane also registers with
+ * Files (images or any other) dropped on it are saved on the server
+ * (`POST /api/run/drop-file`) and their PATHS pasted into the pane — what a
+ * local terminal does on a drop, and how `claude` attaches an image or reads
+ * a file. The pane also registers with
  * `lib/panePaste.ts`, so a diff-line comment from the Changes panel can be
  * pasted into whichever of the workspace's panes was focused last.
  * Keyboard: the terminal keeps Tab and Shift+Tab (claude cycles its permission
@@ -46,7 +47,7 @@ import { terminalThemeFor } from "../../lib/terminalTheme";
 import { api } from "../../lib/api";
 import { notePaneFocus, registerPane } from "../../lib/panePaste";
 
-type DropState = "hint" | "uploading" | "failed" | "imagesOnly";
+type DropState = "hint" | "uploading" | "failed";
 
 /** localStorage flag for xterm's screen-reader mode (a Settings toggle can set it later). */
 export const SCREEN_READER_KEY = "agenthub.terminal.screenReader";
@@ -183,13 +184,13 @@ export function TerminalView({ runId, wsBaseUrl, onExit, autoFocus = true }: Ter
     if (!hasFiles(e)) return; // dragged text keeps xterm's own handling
     e.preventDefault();
     dragDepth.current = 0;
-    const images = Array.from(e.dataTransfer.files).filter((f) => f.type.startsWith("image/"));
-    if (images.length === 0) return flash("imagesOnly");
+    const files = Array.from(e.dataTransfer.files);
+    if (files.length === 0) return;
     setDrop("uploading");
     try {
-      const saved = await Promise.all(images.map((f) => api.run.dropImage(f)));
+      const saved = await Promise.all(files.map((f) => api.run.dropFile(f)));
       // paste(), not a raw send: it honours bracketed-paste mode, so claude
-      // sees one pasted path rather than typed keystrokes.
+      // sees pasted paths rather than typed keystrokes.
       termRef.current?.paste(saved.map((r) => r.path).join(" ") + " ");
       termRef.current?.focus();
       setDrop(null);
@@ -650,9 +651,7 @@ export function TerminalView({ runId, wsBaseUrl, onExit, autoFocus = true }: Ter
         <div
           data-testid="terminal-drop"
           className={`pointer-events-none absolute inset-2 flex items-center justify-center rounded-lg border-2 border-dashed bg-black/50 text-sm font-medium ${
-            drop === "failed" || drop === "imagesOnly"
-              ? "border-red-400 text-red-300"
-              : "border-sky-400 text-sky-200"
+            drop === "failed" ? "border-red-400 text-red-300" : "border-sky-400 text-sky-200"
           }`}
         >
           {t(`drop.${drop}`)}