fix(lsp): move tdd_issue tags before Feature keyword in dos protection feature

The @tdd_issue and @tdd_issue_7161 tags were placed inside the Feature
description body (indented after Feature:), where Behave treats them as
free-text, not tags. The parser fails at the plain-text description line
that follows ("Prevent resource exhaustion...") because it entered the
taggable_statement state after seeing the @-prefixed lines.

Moving both tags to before the Feature: line makes them proper
feature-level tags. All 9 scenarios inherit @tdd_issue via effective_tags,
satisfying the validate_tdd_tags() rule that every @tdd_issue_N scenario
must also carry @tdd_issue. All 9 scenarios now pass.

Refs: #7161

features/lsp_discovery_dos_protection.feature

@@ -1,6 +1,6 @@
+@tdd_issue
+@tdd_issue_7161
 Feature: LSP language discovery DoS protection
-  @tdd_issue
-  @tdd_issue_7161
   Prevent resource exhaustion attacks via directory traversal limits.
   Issue #7161: Resource exhaustion DoS in LSP language discovery.