Fix bqrs_interpret: defensive coercion for file parameter array/bracket handling

Some MCP clients send the file parameter as a JSON-encoded array string
like '["/path/to/file.bqrs"]' or as an actual array instead of a plain
string. The handler now defensively detects both cases and extracts the
clean file path.

TDD: Added 2 regression tests for JSON-encoded array strings and actual
array values passed as the file parameter.

Agent-Logs-Url: https://github.com/advanced-security/codeql-development-mcp-server/sessions/6ff74bab-c637-4e18-a5dc-92e3065583f4

Co-authored-by: data-douser <70299490+data-douser@users.noreply.github.com>

Author: Copilot

server/dist/codeql-development-mcp-server.js

@@ -187355,7 +187355,17 @@ function registerCLITool(server, definition) {
           positionalArgs = [...positionalArgs, ...files];
         }
         if (file && name.startsWith("codeql_bqrs_")) {
-          positionalArgs = [...positionalArgs, file];
+          let cleanFile = Array.isArray(file) ? String(file[0]) : String(file);
+          if (cleanFile.startsWith("[") && cleanFile.endsWith("]")) {
+            try {
+              const parsed = JSON.parse(cleanFile);
+              if (Array.isArray(parsed) && parsed.length > 0) {
+                cleanFile = String(parsed[0]);
+              }
+            } catch {
+            }
+          }
+          positionalArgs = [...positionalArgs, cleanFile];
         }
         if (qlref && name === "codeql_resolve_qlref") {
           positionalArgs = [...positionalArgs, qlref];