feat: add --runtime to notte functions run

[giordano-lucas]

What

Adds --runtime standard|extended to notte functions run.

Why

The regenerated spec in #97 grew a runtime field on RunFunctionRequest:

// Runtime standard uses Lambda; extended uses the configured AgentCore runtime.
Runtime *RunFunctionRequestRuntime `json:"runtime,omitempty"`

But functions run bypasses the generated client and hand-builds its request body (internal/cmd/functions.go, the manual POST /functions/{function_id}/runs/start entry in endpoint-coverage.txt), so the field was unreachable from the CLI — regenerating alone never surfaces it. functions run also has no *_flags.gen.go, so the flag generator won't pick it up on a future regen either.

How

• Sent only when the user passes it, matching --no-stream: the server picks the runtime otherwise, and transmitting its current choice would pin today's behaviour into the client.
• An unknown value is rejected locally (invalid --runtime "lambda": expected standard or extended) rather than becoming a 422. The two values reference the generated api.Standard / api.Extended constants, but the set is hand-written — if the spec grows a third runtime, the switch needs an edit. Flagged in a comment at the site.
• Shell completion suggests both values.

Testing

• TestFunctionRun_SendsRuntimeOnlyWhenSet — omit / standard / extended
• TestFunctionRun_RejectsUnknownRuntime — asserts no request is sent on a bad value
• go test ./..., make check-endpoints, make check-skills, make lint all clean on top of main.

Note for reviewers

Unrelated but adjacent: the hand-built body sends "function_id", while the spec's RunFunctionRequest declares workflow_id. Either the API accepts both or the field is ignored and the path ID is what counts. Deliberately not touched here — worth confirming before more fields go into that map.

🤖 Generated with Claude Code

[greptile-apps]

Confidence Score: 4/5

The implementation appears safe to merge, with a non-blocking test gap around the user-facing Cobra flag wiring.

Summary

• Preserves server-selected runtime behavior when the flag is omitted.
• Rejects unsupported values before issuing an API request.
• Adds request-body tests for omitted, valid, and invalid runtime values.
• The tests do not exercise the actual Cobra flag-parsing path.