Fix config persistence: missing commands, delete handling, multipart

Multiple related bugs in the Save-to-Flash path:

1. Multipart upload was missing the required filename argument,
   causing the backend parser to fail. Added 'config.txt' to the
   form.append call. This was likely the primary reason Save-to-Flash
   was unreliable.

2. Web UI was not pausing its polling interval during flash write,
   causing CPU contention and intermittent crashes. Added isSaving
   lock and clearInterval before sendConfig.

3. conf_cmds whitelist was incomplete. Added: syslog, passwd, pvid,
   ingress, port name, lag, laghash, isolate, stp, igmp, mtu, bw,
   vlan N mgmt, vlan N d.

4. VLAN regex blocked named VLANs. New pattern allows optional name
   (starts with letter, matching CLI parser semantics).

5. vlan N d (delete) was not persisted. parseConf now removes the
   matching vlan N ... entry from configuration[] when seeing a
   delete command, without storing the delete itself. Result: the
   saved config describes the end state.

6. configuration[] was not cleared between flashSave invocations,
   leading to stale entries from prior interactions.

7. conf_overwrite boundary fix: 'pvid 1' no longer matches 'pvid 10'
   etc. Added trailing space in startsWith check.

8. All conf_cmds patterns now anchored with ^...$ for full-line
   match. parseConf normalizes whitespace before testing.

9. Port range widened to \d{1,2} so ports 11+ are accepted.

Structural fixes (1, 2, 6, 7, 8) ported from mcaptur's closed PR #219;
remaining fixes (3, 4, 5, 9) and overall regex strategy are new.

html/config.js

@@ -1,35 +1,83 @@
 var configInterval = Number();
 var configuration = [];
 const conf_cmds = [
-  /ip\s+(\d{1,3}\.){3}\d{1,3}/, /gw\s+(\d{1,3}\.){3}\d{1,3}/, /netmask\s+(\d{1,3}\.){3}\d{1,3}/,
-  /eee(\s+\d)?\s+(on|off)/, /mirror(\s+(\d|10))(\s+(\d|10)(t|r)?)+/, /vlan\s+(\d{1,4})(\s+(\d|10)(t|u)?)+/
+  /^ip\s+(\d{1,3}\.){3}\d{1,3}$/,
+  /^ip\s+dhcp$/,
+  /^gw\s+(\d{1,3}\.){3}\d{1,3}$/,
+  /^netmask\s+(\d{1,3}\.){3}\d{1,3}$/,
+  /^syslog\s+(on|off)$/,
+  /^syslog\s+ip\s+(\d{1,3}\.){3}\d{1,3}$/,
+  /^passwd\s+\S+$/,
+  /^vlan\s+\d{1,4}\s+d$/,
+  /^vlan\s+\d{1,4}\s+mgmt$/,
+  /^vlan\s+\d{1,4}(\s+[a-zA-Z]\w*)?(\s+\d{1,2}[tu]?)+$/,
+  /^pvid\s+\d{1,2}\s+\d{1,4}$/,
+  /^ingress(\s+\d{1,2}[tua])+$/,
+  /^ingress\s+[tua]$/,
+  /^port\s+\d{1,2}\s+name\s+\S+$/,
+  /^eee(\s+\d{1,2})?\s+(on|off)$/,
+  /^mirror(\s+\d{1,2})(\s+\d{1,2}[tr]?)+$/,
+  /^lag\s+\d(\s+\d{1,2})+$/,
+  /^laghash\s+\d(\s+\w+)+$/,
+  /^isolate\s+\d{1,2}(\s+(off|\d{1,2}))+$/,
+  /^stp\s+(on|off)$/,
+  /^igmp\s+(on|off)$/,
+  /^mtu\s+\d{1,2}\s+\d+$/,
+  /^bw\s+(in|out)\s+\d{1,2}\s+\S+$/,
 ];
 const conf_overwrite = [
-  /ip/, /gw/, /netmask/, /eee\s+\w+/, /eee(\s+\w)/, /mirror/, /vlan\s+(\d{1,4})/
+  /^ip\b/,
+  /^gw\b/,
+  /^netmask\b/,
+  /^syslog\s+ip\b/,
+  /^syslog\b/,
+  /^passwd\b/,
+  /^vlan\s+\d{1,4}\b/,
+  /^pvid\s+\d{1,2}\b/,
+  /^ingress\b/,
+  /^port\s+\d{1,2}\s+name\b/,
+  /^eee\s+\d{1,2}\b/,
+  /^eee\b/,
+  /^mirror\b/,
+  /^lag\s+\d+\b/,
+  /^laghash\b/,
+  /^isolate\s+\d{1,2}\b/,
+  /^stp\b/,
+  /^igmp\b/,
+  /^mtu\s+\d{1,2}\b/,
+  /^bw\s+(in|out)\s+\d{1,2}\b/,
 ];
 
 function parseConf(s){
   var a = s.split(/\r\n|\n/);
-    for (var l = 0; l < a.length; l++) {
-      if (!a[l].length || a[l] == "\n" || a[l] == "\r\n")
-        continue;
-      console.log(l + ' --> ' + a[l]);
-      var ignore = true;
-      for (const x of conf_cmds)
-        if (x.test(a[l])) ignore = false;
-      if (ignore) continue;
-      for (const x of conf_overwrite) {
-        if (x.test(a[l])) {
-          console.log("Match ", x, " to ", a[l]);
-          m = a[l].match(x);
-          console.log("Starts with ", m[0]);
-          configuration = configuration.filter(item => !(item.startsWith(m[0])));
-        }
-      }
-      configuration.push(a[l]);
+  for (var l = 0; l < a.length; l++) {
+    var line = a[l].trim().replace(/\s+/g, ' ');
+    if (!line.length) continue;
+    const deleteMatch = line.match(/^vlan\s+(\d{1,4})\s+d$/);
+    if (deleteMatch) {
+      const prefix = "vlan " + deleteMatch[1] + " ";
+      configuration = configuration.filter(c =>
+        c !== "vlan " + deleteMatch[1] && !c.startsWith(prefix));
+      continue;
     }
-    console.log("Configuration now:");
-    for (const x of configuration) { console.log(x); }
+    console.log(l + ' --> ' + line);
+    var ignore = true;
+    for (const x of conf_cmds)
+      if (x.test(line)) { ignore = false; break; }
+    if (ignore) continue;
+    for (const x of conf_overwrite) {
+      if (x.test(line)) {
+        let m = line.match(x);
+        let matchStr = m[0];
+        configuration = configuration.filter(item =>
+          !(item === matchStr || item.startsWith(matchStr + " ")));
+        break;
+      }
+    }
+    configuration.push(line);
+  }
+  console.log("Configuration now:");
+  for (const x of configuration) { console.log(x); }
 }
 
 async function fetchConfig() {