feat(split_out): support dotted paths so fan-out can reach nested arrays

[graycyrus]

split_out did a single-level item.json.get(path), so it couldn't reach an array nested inside a tool_call's {json,text,raw} envelope — e.g. GMAIL_FETCH_EMAILS returns its list at data.messages, unreachable as a top-level key, so split emitted a single null item and nulled the whole downstream fan-out.

resolve_dotted_path() now walks one object key per .-separated segment, so path="json.data.messages" traverses envelope → tool result → the array. Backward compatible: single-segment paths (path="items") unchanged; missing intermediate key → Null (as before). Bump 0.5.0 → 0.5.1.

Consumed by OpenHuman's Workflows builder, which now grounds split_out.path in the tool's real nested output path.

Summary by CodeRabbit

• New Features

  • Support for dotted paths when selecting nested JSON data, making it easier to read deeply nested values.
  • Nested arrays can now be expanded into separate output items while keeping item pairing intact.

• Bug Fixes

  • Missing intermediate or leaf keys now return a single null result instead of failing or returning unexpected data.

• Chores

  • Updated the package version to 0.5.1.

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a dotted-path resolution helper (resolve_dotted_path) to SplitOutNode for traversing nested JSON keys, updates execute to use it when a path is configured, adds corresponding tests, and bumps the crate version from 0.5.0 to 0.5.1.

Changes

SplitOutNode Dotted Path Support

Layer / File(s)	Summary
Dotted path resolver and execute wiring src/nodes/control_flow/split_out.rs	Adds resolve_dotted_path helper to traverse .-separated JSON keys, returning Null on missing segments; execute now uses it for non-empty path configs instead of a single-level lookup.
Dotted path test coverage src/nodes/control_flow/split_out.rs	Adds tests verifying array fan-out via nested dotted paths with correct paired_item indices, and Null output when an intermediate key is missing.
Crate version bump Cargo.toml	Bumps package version from 0.5.0 to 0.5.1.

Estimated code review effort: 2 (Simple) | ~10 minutes

Poem

A dot, then a dot, I hop through the keys,
Nested JSON gardens, easy as breeze,
Missing a path? I land on a Null,
Tests all pass — my burrow is full!
🐰 v0.5.1, hoppy and true! 🥕

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the main change: SplitOut now supports dotted paths to fan out nested arrays.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

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[coderabbitai]

🧹 Nitpick comments (1)

src/nodes/control_flow/split_out.rs (1)

13-32: 📐 Maintainability & Code Quality | 🔵 Trivial | 💤 Low value

Factor the dotted-path walk into one helper

There’s duplicated dotted-path traversal in src/nodes/control_flow/split_out.rs and src/expr.rs::resolve_path. If these semantics should stay identical, extract a shared helper instead of maintaining two copies.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@src/nodes/control_flow/split_out.rs` around lines 13 - 32, The dotted-path
traversal logic is duplicated between split_out’s resolve_dotted_path and
expr::resolve_path, so update the code to use one shared helper for path
walking. Extract the common dotted-path resolution behavior into a reusable
function or utility, then have both split_out and expr::resolve_path call it so
the semantics stay identical in one place. Keep the existing handling for
single-segment keys, missing segments returning Null, and nested object
traversal unchanged.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@src/nodes/control_flow/split_out.rs`:
- Around line 13-32: The dotted-path traversal logic is duplicated between
split_out’s resolve_dotted_path and expr::resolve_path, so update the code to
use one shared helper for path walking. Extract the common dotted-path
resolution behavior into a reusable function or utility, then have both
split_out and expr::resolve_path call it so the semantics stay identical in one
place. Keep the existing handling for single-segment keys, missing segments
returning Null, and nested object traversal unchanged.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: a7bdfc89-d19d-4e12-b61e-b27f44bee9f3

📥 Commits

Reviewing files that changed from the base of the PR and between 0afab64 and 1a2f6e9.

📒 Files selected for processing (2)

• Cargo.toml
• src/nodes/control_flow/split_out.rs