Fix ty type errors with ignore comments and isinstance assertions

[Copilot]

Resolved 21 ty type errors across 8 locations by adding type ignore comments where ty's type narrowing is insufficient and isinstance assertions where they improve type safety.

Changes

Source code:

• _files/_parsing/__init__.py:244 - Added ty: ignore[invalid-assignment] for dict assignment after isinstance check
• _files/_serialization.py:380 - Extended ignore to include not-iterable for *data unpacking
• _files/files.py:1196 - Added ty: ignore[invalid-argument-type] for ret[None] access

Tests:

• test_files.py:101 - Added ty: ignore[invalid-assignment] for copy-on-write list mutation test
• test_parsing/test_intermediate.py:164-169 - Added isinstance checks for tuple/list and dict, with ignore comments for subsequent subscript operations where type narrowing remains insufficient

All fixes target specific ty error codes on lines where type inference limitations prevent proper type narrowing despite runtime assertions.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• astral.sh
  • Triggering command: /usr/bin/curl curl -LsSf REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
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Original prompt

Fix ty errors on the latest version by adding the relevant isinstance assertions, otherwise fixing the error, or (if no other option) ignoring the specific ty code(s) on the offending line. Keep doing it until no ty errors remain

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