fix(kiro): recover native invoke tool calls and keep trailing system tools

[tonybase]

Summary

The Kiro-backed model (AI_EDITOR origin) frequently emits tool calls as inline text in Claude's XML <invoke name="..."> format — using Kiro IDE's own tool names — instead of structured toolUseEvent events. Left as plain text, the client never sees a tool_use block, so no tool runs and the model starts hallucinating fake tool results. This PR recovers those calls and fixes the upstream condition that triggers them.

Changes

Native <invoke> tool-call recovery (kiro_claude_tools.go, kiro_executor.go)

• Parse <invoke> / <parameter> blocks (antml: namespace tolerated), preserving JSON types for array/number params.
• Map native names onto the client's canonical Claude tools:
  • readFile/fsRead/readMultipleFiles → Read
  • grepSearch → Grep (with includePattern → glob)
  • fileSearch → Glob
  • listDirectory → Bash (ls / ls -R)
  • writeFile/fsWrite/createFile → Write
  • strReplaceEditor/editFile → Edit
  • executeBash/runCommand → Bash
  • unknown tools pass through unchanged.
• Wired into both the buffered (parseEventStream) and streaming (streamToChannel) paths. InvokeStreamParser buffers partial tags across chunk boundaries and flushes incomplete markup as text so nothing is dropped.
• Override end_turn → tool_use when calls are recovered, so the client actually runs them. Dedup is shared with the structured tool-use path.

Trailing in-array system message normalization (kiro_claude_request.go)

• Claude Code's mid-conversation-system beta (mid-conversation-system-2026-04-07) can place role:"system" messages inside the messages array, including as the final entry. Kiro has no system role, so these are rewritten as user content wrapped in <system-reminder> tags before merging.
• Critically, a trailing system message must still produce a current user message — otherwise no tool specs attach to currentMessage.userInputMessageContext and the model, seeing no tools, hallucinates text-format tool calls (the root cause of the recovery above).

New Kiro model aliases + definitions (oauth_model_alias_defaults.go, model_definitions.go)

• Claude Sonnet 5, Opus 4.8, Fable 5.

Testing

• gofmt -l internal/ — clean
• go build ./cmd/server — passes
• go test ./internal/translator/kiro/... ./internal/runtime/executor/... ./internal/config/... ./internal/registry/... — passes
• New unit tests: kiro_claude_tools_test.go (parse/map/stream), plus TestBuildKiroPayload_TrailingSystemMessageKeepsTools.

🤖 Generated with Claude Code