build(deps-dev): bump ruff from 0.15.20 to 0.16.0

[dependabot]

Bumps ruff from 0.15.20 to 0.16.0.

Release notes

Sourced from ruff's releases.

0.16.0

Release Notes

Released on 2026-07-23.

Check out the blog post for a migration guide and overview of the changes!

Breaking changes

• Ruff now enables a much larger set of rules by default (413, up from 59). See the blog post for more details and the new Default Rules page for a full listing of the enabled rules. Note that this is primarily an expansion, but 18 of the more opinionated pycodestyle (E) and pyflakes (F) rules have been removed from the default set: E401, E402, E701, E702, E703, E711, E712, E713, E714, E721, E731, E741, E742, E743, F403, F405, F406, and F722.

• Ruff can now format Python code blocks in Markdown files and will do this by default. See the documentation for more details.

• Ruff now supports ruff: ignore comments at the ends of lines, like noqa comments, or on the line preceding a diagnostic. For example, these both suppress an unused-import (F401) diagnostic:

  import math  # ruff: ignore[F401]
  ruff: ignore[F401]
  import os

• Fixes are now shown in check and format --check output:

  ❯ ruff format --check .
  unformatted: File would be reformatted
   --> try.md:1:1
    |
  1 | ```python
    - import   math
  2 + import math
  3 | ```
    |
  1 file would be reformatted

  This example also shows off the Markdown formatting.

• format --check now supports the same output formats as the linter, including the github and gitlab outputs for rendering annotations in CI:

  ❯ ruff format --check --output-format github .
  ::error title=ruff (unformatted),file=try.md,line=2,col=8,endLine=2,endColumn=10::try.md:2:8: unformatted: File would be reformatted

  See the CLI help or documentation for the full list of supported formats.

• The filename, location, end_location, fix.edits[].location, and fix.edits[].end_location fields in the JSON output format may now be null rather than defaulting to the empty string and row 1, column 1, respectively.

... (truncated)

Changelog

Sourced from ruff's changelog.

0.16.0

Released on 2026-07-23.

Check out the blog post for a migration guide and overview of the changes!

Breaking changes

• Ruff now enables a much larger set of rules by default (413, up from 59). See the blog post for more details and the new Default Rules page for a full listing of the enabled rules. Note that this is primarily an expansion, but 18 of the more opinionated pycodestyle (E) and pyflakes (F) rules have been removed from the default set: E401, E402, E701, E702, E703, E711, E712, E713, E714, E721, E731, E741, E742, E743, F403, F405, F406, and F722.

• Ruff can now format Python code blocks in Markdown files and will do this by default. See the documentation for more details.

• Ruff now supports ruff: ignore comments at the ends of lines, like noqa comments, or on the line preceding a diagnostic. For example, these both suppress an unused-import (F401) diagnostic:

  import math  # ruff: ignore[F401]
  ruff: ignore[F401]
  import os

• Fixes are now shown in check and format --check output:

  ❯ ruff format --check .
  unformatted: File would be reformatted
   --> try.md:1:1
    |
  1 | ```python
    - import   math
  2 + import math
  3 | ```
    |
  1 file would be reformatted

  This example also shows off the Markdown formatting.

• format --check now supports the same output formats as the linter, including the github and gitlab outputs for rendering annotations in CI:

... (truncated)

Commits

• a2635fd Bump 0.16.0 (#27136)
• 3433449 [ty] Reuse full call diagnostics for implicit setter calls (#27115)
• 2240070 Reflect ruff: ignore and --add-ignore stabilization in documentation (#27...
• 17ef711 Stabilize --add-ignore (#27125)
• ef912bb Add newly stabilized rules to defaults (#27055)
• b30f040 Stabilize new default rules (#27035)
• bcd70c5 Exclude Markdown files from format-dev runs (#27052)
• 87e51e2 Fix format --check spans for syntax errors (#27045)
• afe2723 [flake8-gettext] Stabilize qualified-name and built-in binding resolution (...
• a9702d8 [flake8-bandit] Stabilize string literal binding resolution (S310) (#26944)
• Additional commits viewable in compare view

[Chris-ObtuseAI]

Measured: this is a pin update plus ~935 lint fixes, not a pin update

Probed with uvx ruff@0.16.0 in an ephemeral environment (never touched the project venv):

ruff 0.15.20 (pinned)      0 errors  — clean
ruff 0.16.0              935 errors, 524 auto-fixable

All 935 are new in 0.16. Top rules:

count	rule
216	RUF100 unused-noqa	auto-fixable
160	I001 unsorted-imports	auto-fixable
119	SIM117 multiple-with-statements
99	TRY004 type-check-without-type-error
67	FURB162 fromisoformat-replace-z
53	BLE001 blind-except	review-required
32	UP035 deprecated-import	auto-fixable

The hazard is BLE001

This codebase uses except Exception deliberately for fail-closed behaviour — the audit and evidence machinery depends on refusing rather than propagating. Bulk-fixing those 53 would attack the exact property the whole design rests on. Any migration must treat BLE001 as review-required, never auto-fixed.

Two findings worth harvesting regardless of this bump

• 216 RUF100 — the repo carries 216 # noqa suppressions for rules that no longer fire. Dead scar tissue; removing them is safe and clarifying.
• 67 FURB162 — .replace("Z", "+00:00") before fromisoformat appears throughout. Python 3.11+ parses Z natively.

And the pin sites, since dependabot only updates two of five

1. pyproject.toml
2. uv.lock                                <- dependabot does this
3. requirements-validation.lock           uv export --only-group validation --no-annotate
4. requirements-runtime.lock              uv export --no-default-groups
5. scripts/validate_release_python.py:41  EXPECTED_TOOL_VERSIONS   <- the one that gets missed

--no-annotate matters; without it the export differs byte-wise and validation_lock_reproducible fails, which is the gate currently red here.

Caution: never run uv run --frozen or uv sync while the forward service is live — it rebuilds .venv, fails on the file lock, and leaves it partially deleted. uv lock and uv export are safe.

Diagnosed 2026-08-02 alongside #18 (hidden two-major Vite migration) and #36 (breaking Rust API change). The three open dependabot PRs are three different problems.

[dependabot]

Superseded by #69.