#16328: fix: add 'does not support tools' to format error patterns for failover

This PR adds the error string "does not support tools" to the format error patterns. This is commonly returned by Ollama (400 Bad Request) when a model does not support tool use. Recognizing this error allows OpenClaw to correctly trigger a model fallback instead of stopping with an unhandled error. <!-- greptile_comment --> <h3>Greptile Summary</h3> Adds the `"does not support tools"` string to `ERROR_PATTERNS.format` in `src/agents/pi-embedded-helpers/errors.ts`, enabling OpenClaw to recognize Ollama's 400 Bad Request error when a model lacks tool support and trigger model failover instead of surfacing an unhandled error. - The new pattern is a single string addition to the existing `format` error patterns array, consistent with how other format errors (e.g., `"invalid request format"`) are already handled. - `matchesErrorPatterns` lowercases input before comparison, so the match is case-insensitive. - No test cases were added for the new pattern — consider adding a test in `pi-embedded-helpers.iscloudcodeassistformaterror.e2e.test.ts` and `pi-embedded-helpers.classifyfailoverreason.e2e.test.ts` to cover the Ollama-specific error string. <h3>Confidence Score: 5/5</h3> - This PR is safe to merge — it's a minimal, additive change to an error pattern list with no risk of breaking existing behavior. - The change adds a single string to an existing error pattern array, following the exact same convention as all other entries. The matching logic in matchesErrorPatterns is well-tested and case-insensitive. The new pattern correctly enables failover for Ollama models that don't support tools. No logical, security, or syntax issues. - No files require special attention. _{Last reviewed commit: e143b4b} <!-- greptile_other_comments_section --> _{(2/5) Greptile learns from your feedback when you react with thumbs up/down!} <!-- /greptile_comment -->