chore(ci): consolidate GHA workflows and reserve SDK bumps for dedicated workflow

Delete ci-failure-resolver-with-agent.yml (redundant with pr-fixer.yml)
and exclude anthropic/claude-agent-sdk from Dependabot so PR ambient-code#987's
sdk-version-bump workflow is the single source of SDK updates.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 2 people

.github/dependabot.yml

@@ -6,7 +6,9 @@ updates:
     schedule:
       interval: "weekly"
     open-pull-requests-limit: 10
-    # Auto-merge minor and patch updates
+    ignore:
+      - dependency-name: "anthropic"
+      - dependency-name: "claude-agent-sdk"
     pull-request-branch-name:
       separator: "-"
     commit-message: