fix(cli-tools): tolerate JSONC configs in CLI tool settings routes

readConfig/readSettings/readJson across all CLI tool settings routes used
JSON.parse() but only caught ENOENT, re-throwing SyntaxError on any
corrupted or JSONC-formatted config file. The API would return 500, which
the UI misinterpreted as "tool not installed."

This patch:
- strips trailing commas before parsing (handles JSONC from opencode, etc.)
- returns null on any parse error instead of re-throwing, so the UI shows
  "installed but not configured" (accurate) instead of "not installed"
- applies the same fix to all 8 affected routes: opencode, openclaw, kilo,
  droid, cowork, copilot, claude, and cline

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/api/cli-tools/copilot-settings/route.js

@@ -21,10 +21,12 @@ const getConfigPath = () => {
 const readConfig = async () => {
   try {
     const content = await fs.readFile(getConfigPath(), "utf-8");
-    return JSON.parse(content);
+    // Tolerate JSONC (trailing commas) and treat unparseable files as "no config"
+    // rather than throwing a 500 that the UI misreads as "tool not installed".
+    const stripped = content.replace(/,(\s*[}\]])/g, "$1");
+    return JSON.parse(stripped);
   } catch (error) {
-    if (error.code === "ENOENT") return null;
-    throw error;
+    return null;
   }
 };