upgrade: update dependency flutter to v3.27.0

[renovate]

This PR contains the following updates:

Package	Update	Change
flutter (source)	minor	3.24.5 -> 3.27.0

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Release Notes

flutter/flutter (flutter)

v3.27.0

Compare Source

Initial stable release.

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Configuration

📅 Schedule: Branch creation - "every weekend" in timezone Asia/Tokyo, Automerge - At any time (no schedule defined).

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.36%. Comparing base (e836f19) to head (03b759b).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #617   +/-   ##
=======================================
  Coverage   98.36%   98.36%           
=======================================
  Files          22       22           
  Lines         917      917           
=======================================
  Hits          902      902           
  Misses         15       15           

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