fix(issue): Handle object headers in buildRequestMarkdown

[sentry]

This PR addresses CLI-297, a TypeError: .for is not iterable occurring in buildRequestMarkdown when processing issue request data.

Problem:
The buildRequestMarkdown function in src/lib/formatters/human.ts assumed that requestEntry.data.headers would always be an array of [key, value] tuples, suitable for for...of iteration. However, the Sentry API can sometimes return headers as a plain object (Record<string, string>), leading to a TypeError when attempting to iterate over it.

Solution:

1. Type Definition Update: The type definition for RequestEntry.data.headers in src/types/sentry.ts has been updated to [string, string][] | Record<string, string> | null to accurately reflect the possible data shapes from the API.
2. Runtime Normalization: In buildRequestMarkdown, a check has been added to determine if data.headers is an array. If it's not an array (implying it's an object), Object.entries() is used to convert the object into an array of [key, value] tuples before iteration. This ensures that the for...of loop can correctly process headers regardless of their original format.

Fixes CLI-297

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

[linear-code]

CLI-297

[github-actions]

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[github-actions]

Codecov Results 📊

✅ Patch coverage is 100.00%. Project has 5369 uncovered lines.
❌ Project coverage is 81.77%. Comparing base (base) to head (head).

Files with missing lines (1)

File	Patch %	Lines
src/lib/formatters/human.ts	100.00%	⚠️ 1 partials

Coverage diff

@@            Coverage Diff             @@
##          main       #PR       +/-##
==========================================
- Coverage    81.78%    81.77%    -0.01%
==========================================
  Files          424       424         —
  Lines        29452     29453        +1
  Branches     19190     19192        +2
==========================================
+ Hits         24085     24084        -1
- Misses        5367      5369        +2
- Partials      1999      2001        +2

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