feat: allow renaming rule before creation

[uinstinct]

Description

Show a dialog when adding a new rule so that it can be renamed. When left empty, the previous "new-rule.md" is applied.

closes #8663

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Checklist

• [] I've read the contributing guide
• [] The relevant docs, if any, have been updated or created
• [] The relevant tests, if any, have been updated or created

Screen recording or screenshot

feat.mp4

Tests

[ What tests were added or updated to ensure the changes work as expected? ]

---

Summary by cubic

Let users name a rule file before creation via a new dialog. Works for both workspace and global rules, with sanitized filenames and updated core handling.

• New Features
  • Added AddRuleDialog with input, validation, and create/cancel actions.
  • RulesSection now opens the dialog; the dialog posts baseFilename to core for workspace or global rule creation.
  • Extended core protocol to accept baseFilename for "config/addLocalWorkspaceBlock" and "config/addGlobalRule".
  • Updated file creation to support a base filename override, strip extensions, sanitize rule names, and ensure a unique file path; falls back to default names if the sanitized result is empty.

^{Written for commit b6a8be5. Summary will update automatically on new commits.}

[cubic-dev-ai]

2 issues found across 5 files

Prompt for AI agents (all 2 issues)

Understand the root cause of the following 2 issues and fix them.


<file name="gui/src/components/dialogs/AddRuleDialog.tsx">

<violation number="1" location="gui/src/components/dialogs/AddRuleDialog.tsx:32">
Leaving the dialog empty is supposed to fall back to the previous `new-rule.md`, but the submit handler rejects empty inputs so the fallback can never trigger. Default the trimmed value to `&quot;new-rule.md&quot;` instead of treating it as an error.</violation>

<violation number="2" location="gui/src/components/dialogs/AddRuleDialog.tsx:81">
The Create button is permanently disabled when the input is blank, so users can’t exercise the documented “leave empty to use new-rule.md” behavior. Allow submission when empty and only gate on `isSubmitting`.</violation>
</file>

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