fix(arg-parsing): handle space-separated event IDs (CLI-1HT)

[sentry]

Previously, the splitNewlineArg function in src/lib/arg-parsing.ts only split strings by newline characters (\n). This caused issues when AI agents (and potentially users) provided multiple event IDs separated by spaces as a single argument, leading to a ValidationError: Invalid Event ID: contains a space. because the entire string was treated as one ID.

This change modifies splitNewlineArg to split on any whitespace (/\s+/), ensuring that event IDs separated by spaces, tabs, or newlines are correctly parsed into individual arguments. To comply with linting rules (lint/performance/useTopLevelRegex), the regex literal was moved to a top-level constant WHITESPACE_RE.

Fixes CLI-1HT

_{Comment @sentry <feedback> on this PR to have Autofix iterate on the changes.}

[github-actions]

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[sentry]

Bug: The change to split arguments on any whitespace (/\s+/) in splitNewlineArg will incorrectly break up project display names containing spaces, like "org/My Project".
_{Severity: HIGH}

Suggested Fix

The fix should be more targeted to only apply to the arguments that are expected to be lists (like event IDs), while preserving the original behavior for arguments that could be project display names. This might involve making the splitting behavior conditional or applying it at a different stage of parsing, after project arguments have already been identified and handled. For example, only apply the whitespace split within the event view command's argument handling, not globally in splitNewlineArg.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: src/lib/arg-parsing.ts#L1247

Potential issue: The function `splitNewlineArg` was changed to split arguments on any
whitespace (`/\s+/`) to support space-separated IDs. However, this introduces a
regression. The CLI supports project display names with spaces (e.g., `"org/My
Project"`), and has logic to handle them as a single argument. When such a display name
is passed as a single string, which is a common scenario for programmatic callers like
AI agents, the new logic will incorrectly split it into multiple arguments (e.g.,
`["org/My", "Project"]`). This breaks downstream parsing logic which expects a single
project argument, causing command failures.

Also affects:

• src/commands/event/view.ts:179

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[github-actions]

Codecov Results 📊

✅ Patch coverage is 100.00%. Project has 5478 uncovered lines.
✅ Project coverage is 81.69%. Comparing base (base) to head (head).

Coverage diff

@@            Coverage Diff             @@
##          main       #PR       +/-##
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+ Coverage    81.69%    81.69%        —%
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  Files          426       426         —
  Lines        29909     29910        +1
  Branches     19433     19433         —
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+ Hits         24431     24432        +1
- Misses        5478      5478         —
- Partials      2035      2035         —

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