Summary

Removes accidentally repeated words ("the the", "is is") in dartdoc and inline comments across lutter and lutter_tools. Comment-only follow-up to #186319.

No code, public API, or behavior is touched. The fix is mechanical and was verified by re-grepping the modified files.

Changes

• packages/flutter/lib/src/widgets/text_selection.dart: the the start handle -> the start handle; the the end handle -> the end handle
• packages/flutter_tools/lib/src/ios/lldb.dart: dartdoc on _LLDBProcess — [Process] that is is running LLDB -> [Process] that is running LLDB
• packages/flutter_tools/test/host_cross_arch.shard/ios_content_validation_test.dart: This is is the default for CocoaPods -> This is the default for CocoaPods

Tests

No tests added. This is a comment-only change with no executable lines touched. Verified locally by grepping the touched files for residual the the / is is / to to / similar doubled tokens — none remain.

Notes for maintainers

• Pre-launch checklist read; no engineering doc rewrite needed (docs-only).
• No Material or Cupertino source paths are modified, so the active code freeze is not impacted.
• Authored by a human (Nicoreia) with AI tooling assistance, in line with Flutter's AI contribution policy: scope is small, mechanical, and reviewable; no generated logic.

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene page and followed its process for submitting this PR.
• I read and followed the Flutter Style Guide.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.