Strip ANSI sequences from container logs for clean display.

PM2 and similar tools emit VT100 color codes that browsers hide only
partially, leaving artifacts like [32m between table columns. Strip CSI/OSC
escapes when formatting log lines, and harden Docker multiplex demux on the
server so frames are not mis-parsed as text.

app.js

@@ -5560,6 +5560,33 @@ let logsState = {
   containerId: null,
 };
 
+/**
+ * Strip ANSI / VT100 escape sequences from container log text.
+ * Apps like PM2 emit colors as ESC[…m; browsers hide ESC so you see "[32m" junk.
+ */
+function stripAnsi(input) {
+  let s = String(input ?? '');
+  // CSI: ESC [ ... final byte (@-~)
+  s = s.replace(/\u001b\[[\x30-\x3f]*[\x20-\x2f]*[\x40-\x7e]/g, '');
+  // OSC: ESC ] ... BEL or ST (ESC \)
+  s = s.replace(/\u001b\][^\u0007\u001b]*(?:\u0007|\u001b\\)/g, '');
+  // 2-byte escapes: ESC + final
+  s = s.replace(/\u001b[@-Z\\-_]/g, '');
+  // 7-bit CSI without ESC (rare) and C1 CSI (0x9b)
+  s = s.replace(/\u009b[\x30-\x3f]*[\x20-\x2f]*[\x40-\x7e]/g, '');
+  // Orphaned SGR fragments if ESC was already lost: [1;32m or [39m
+  s = s.replace(/\x1b/g, '');
+  s = s.replace(/(?:^|[^\d])\[(?:\d{1,3};)*\d{0,3}[mK]/g, (m) =>
+    m.startsWith('[') ? '' : m[0]
+  );
+  // Clean leftover pure SGR tokens at line start / after space
+  s = s.replace(/(?:^|\s)\[(?:\d{1,3};)*\d{0,3}m/g, (m) => (m[0] === '[' ? '' : m[0]));
+  s = s.replace(/\[(?:\d{1,3};)*\d{0,3}m/g, '');
+  // Other C0 controls except tab/newline
+  s = s.replace(/[\u0000-\u0008\u000B\u000C\u000E-\u001F\u007F]/g, '');
+  return s;
+}
+
 // Detect log level from log line
 function detectLogLevel(line) {
   const lowerLine = line.toLowerCase();
@@ -5577,8 +5604,10 @@ function detectLogLevel(line) {
 
 // Format log line with timestamp and level detection
 function formatLogLine(rawLine) {
-  // Preserve leading spaces; only drop pure empty lines
-  const line = String(rawLine ?? '').replace(/\r$/, '');
+  // Strip ANSI first so colors/tables from PM2 etc. don't leak as "[32m"
+  let line = stripAnsi(String(rawLine ?? ''));
+  // Normalize CR-only progress lines / CRLF
+  line = line.replace(/\r/g, '');
   if (!line.trim()) return null;
 
   const level = detectLogLevel(line);