New nodes: 'Regex Contains', 'Regex Replace', 'Regex Find', 'Regex Find All', and 'Regex Split'

[Keavon]

Category - Text: Regex

• Regex Contains: Checks if a string matches a regex pattern, optionally anchored to start/end.
• Regex Replace: Replaces regex matches with a replacement string (supports capture group references $0, $1, etc.).
• Regex Find: Finds the Nth match of a regex and returns it with its capture groups as a list.
• Regex Find All: Finds all non-overlapping matches of a regex pattern, returning a list.
• Regex Split: Splits a string on a regex separator pattern.

Broken out from #4010.

[cubic-dev-ai]

2 issues found across 8 files

Confidence score: 4/5

• This PR looks safe to merge overall: both reported issues are mid-severity (5/10) and appear to be consistency/process concerns rather than clear runtime breakage.
• The most user-impacting item is in node-graph/nodes/text/src/regex.rs, where regex_find has an empty node category; this can reduce discoverability by keeping it from appearing alongside other regex nodes.
• The note in editor/src/messages/portfolio/document/node_graph/document_node_definitions.rs is a PR-title format enforcement issue (New node(s): ...), which is important for workflow consistency but is not likely to affect product behavior.
• Pay close attention to node-graph/nodes/text/src/regex.rs and editor/src/messages/portfolio/document/node_graph/document_node_definitions.rs - node categorization consistency and required title-format compliance should be corrected.

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="editor/src/messages/portfolio/document/node_graph/document_node_definitions.rs">

<violation number="1" location="editor/src/messages/portfolio/document/node_graph/document_node_definitions.rs:1493">
P2: Custom agent: **PR title enforcement**

PR title for a node-adding change does not use the required dedicated "New node(s): ..." format.</violation>
</file>

<file name="node-graph/nodes/text/src/regex.rs">

<violation number="1" location="node-graph/nodes/text/src/regex.rs:82">
P2: `regex_find` is registered with an empty node category, which can prevent it from appearing with the other regex nodes and makes it inconsistent with the rest of this feature.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[gemini-code-assist]

Code Review

This pull request introduces a new suite of regex-based nodes for the node graph system, including regex_contains, regex_replace, regex_find, regex_find_all, and regex_split, alongside utility traits for index manipulation. The review identified several high-severity type mismatch issues in the node definitions where f64 was incorrectly used instead of i64 for index inputs, as well as medium-severity concerns regarding safe integer handling and logging consistency in the new regex implementation.