fix(devin): catalog-driven model UIDs and tool-result images

[caigee-cmd]

Summary

Track CLIProxyAPI's Devin registry update (v7.3.16 / commit 65459ca) and its tool-result image fix (v7.3.7):

• mapping.go: drop the hardcoded swe-1-7 / swe-1-6 / glm-5-2 suffix tables. The upstream registry drifted — swe-1-7 now only accepts medium (with a separate swe-1-7-lightning id), glm-5-2 levels are [none, max], and swe-1-6 has no thinking. Suffixed chat_model_uids are built purely from catalog thinking.levels, clamped per project rules.
• Default effort: never pick none implicitly — a [none, max] catalog defaults to max; none is only sent when explicitly requested.
• payload.go: tool role messages go through splitContent, so images embedded in tool results reach the upstream prompt (prompt.Images) instead of being flattened away.
• Fixture: refreshed to current upstream — max_completion_tokens 64000, swe-1-7-lightning, glm-5-2 [none,max], image modalities on glm-5-3-flash / swe-1-6.

Test plan

• go test ./internal/providers/devin/... — new assertions cover glm-5-2 (none/max), swe-1-7, swe-1-7-lightning, suffixed passthrough, and tool-result image passthrough
• go test ./... — all green
• git diff --check clean
• Live-account acceptance against a real Devin account (experimental provider; not run here)