fix(types): restrict StreamOptions.objectMode to true (#3686)

[minzunim]

fix(types): restrict StreamOptions.objectMode to true

As discussed in #3686, objectMode is always forced to true internally, so the current any type is misleading. This change updates the definition to true to better reflect the actual behavior.

Closes #3686

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.25%. Comparing base (aac1b0f) to head (585829b).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3784   +/-   ##
=======================================
  Coverage   89.25%   89.25%           
=======================================
  Files          86       86           
  Lines       13583    13583           
  Branches     1584     1584           
=======================================
  Hits        12124    12124           
  Misses       1459     1459           

Flag	Coverage Δ
compression-0	88.36% <ø> (ø)
compression-1	89.23% <ø> (ø)
static-parser-0	86.82% <ø> (ø)
static-parser-1	87.59% <ø> (ø)
tls-0	88.67% <ø> (ø)
tls-1	89.03% <ø> (ø)

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[wellwelwel]

Thanks, @minzunim! 🚀