fix: sshfs polling, WebSocket broadcast, prompt progress bar, resizable stats panel

- log_watcher: add --reopen-log mode (close/reopen each poll) for sshfs/network
  filesystems; fix nonlocal clients bug causing UnboundLocalError on first broadcast;
  fix list(clients) copy to prevent RuntimeError on concurrent set mutation
- log_parser: capture progress=X.XX from prompt timing lines into Metrics.prompt_progress
- frontend: show progress bar during processing_prompt state with PROMPT N% label;
  widen stats panel to 300px; remove model name truncation; add drag handle on
  right border of stats panel to resize between 280px–840px

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/style.css

@@ -139,6 +139,9 @@ body.state-generating #speech-bubble { display: flex; }
 /* loading */
 body.state-loading #progress-wrap { display: flex; }
 
+/* processing_prompt */
+body.state-processing_prompt #progress-wrap { display: flex; }
+
 /* offline */
 body.state-offline #llama { opacity: 0.15; }
 
@@ -237,9 +240,40 @@ body.state-offline #llama { opacity: 0.15; }
   color: var(--amber-dim);
 }
 
+/* ── Resize handle ───────────────────────────────────────────────────────── */
+#resize-handle {
+  position: absolute;
+  right: -6px;
+  top: 0;
+  bottom: 0;
+  width: 12px;
+  cursor: ew-resize;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  opacity: 0.3;
+  transition: opacity 0.15s;
+  user-select: none;
+  z-index: 10;
+}
+#resize-handle:hover,
+#resize-handle.dragging { opacity: 1; }
+#resize-handle::after {
+  content: '';
+  width: 2px;
+  height: 48px;
+  background: var(--amber-dim);
+  border-radius: 1px;
+  box-shadow: -4px 0 0 var(--amber-dim), 4px 0 0 var(--amber-dim);
+}
+@media (orientation: portrait) {
+  #resize-handle { display: none; }
+}
+
 /* ── Stats panel ─────────────────────────────────────────────────────────── */
 #stats-panel {
-  flex: 0 0 220px;
+  position: relative;
+  flex: 0 0 300px;
   background: #0d0d06;
   border: 3px solid var(--amber-dim);
   border-radius: 12px;