fix(models-config): namespace input names per type + truthy error gate

Two issues survived the per-type form-state landing:

1. API Key (and Name / URL) appeared filled across all four
   sub-tabs even though my per-type bindings were correct. Root
   cause: browser autofill. All four tabs' inputs shared
   `name="apiKey"`, `name="name"`, `name="url"` — browsers
   treat same-named password / text fields as the same logical
   field and silently propagate stored credentials across them,
   so the value typed into Google was auto-filled into OpenAI /
   Anthropic / OpenAI-compatible regardless of what the json-render
   `value` binding said. The state was per-type; the DOM input
   was being filled by Chrome/Firefox's autofill heuristic.

   Fix: every Input now has a `name="${type}-${field}"` (e.g.
   `google-apiKey`, `openai-apiKey`, `anthropic-name`). Browsers
   no longer cross-pollinate values.

2. Error Alert visibility used `{ neq: null }` which evaluates
   `value !== null` — visible for `undefined`, `""`, and any
   string. If the seeded `error: null` was missing or got
   shadowed, the panel rendered "Error" with an empty message.

   Fix: switch to `{ $state: ".../error" }` (no comparator).
   The json-render `evaluateCondition` falls back to
   `Boolean(value)` when no comparator is supplied — `null`,
   `undefined`, and `""` all evaluate to false (hidden); only
   a real non-empty string makes the Alert appear.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: mkotelnikov

packages/models-config/src/public/connections-tab-spec.ts

@@ -172,11 +172,15 @@ function tabBodyElements(type: ConnectionType): Record<string, unknown> {
       type: "Heading",
       props: { text: "Headers", level: "h4" },
     },
+    // Input `name` attributes are per-type-prefixed so the browser's
+    // autofill heuristics don't share the value across the four
+    // sub-tabs (otherwise the OpenAI API Key field would be
+    // auto-filled with the value the user typed into Google).
     [`${type}_formName`]: {
       type: "Input",
       props: {
         label: "Name",
-        name: "name",
+        name: `${type}-name`,
         type: "text",
         placeholder: `e.g. ${TYPE_LABEL[type]} (work)`,
         value: { $bindState: `/ui/connectionForms/${type}/name` },
@@ -186,7 +190,7 @@ function tabBodyElements(type: ConnectionType): Record<string, unknown> {
       type: "Input",
       props: {
         label: "API Key",
-        name: "apiKey",
+        name: `${type}-apiKey`,
         type: "password",
         placeholder: "sk-…",
         value: { $bindState: `/ui/connectionForms/${type}/apiKey` },
@@ -196,7 +200,7 @@ function tabBodyElements(type: ConnectionType): Record<string, unknown> {
       type: "Input",
       props: {
         label: urlLabel,
-        name: "url",
+        name: `${type}-url`,
         type: "text",
         placeholder: urlPlaceholder,
         value: { $bindState: `/ui/connectionForms/${type}/url` },
@@ -259,11 +263,11 @@ function tabBodyElements(type: ConnectionType): Record<string, unknown> {
         message: { $state: `/ui/connectionForms/${type}/error` },
         type: "error",
       },
-      // Only render when error is a non-null string. Initial state
-      // seeds `error: null`, action handlers reset to `null` on
-      // success, so this gate hides the panel until a real error
-      // arrives.
-      visible: { $state: `/ui/connectionForms/${type}/error`, neq: null },
+      // Truthy gate — `evaluateCondition` falls back to
+      // `Boolean(value)` when no comparator (eq/neq/gt/…) is
+      // supplied. Hidden for null, undefined, and "" — visible
+      // only when an action handler has written a real string.
+      visible: { $state: `/ui/connectionForms/${type}/error` },
     },
     [`${type}_formConnect`]: {
       type: "Button",