feat(summary): show how to exclude a read-and-written file in --last-details

[wan9chi]

Motivation

User feedback: vp run --last-details showed Not cached: read and wrote 'node_modules/.fate-graphql-t8W5Ii/usage.ts' for a temporary file that the user's test suite had created and deleted. The message didn't say that the task read and wrote the file, so the user took it for a Vite+ cache file. It also didn't say how to make the task cacheable.

Changes

--last-details now says the task read and wrote the file, and shows the cache entries that exclude it:

→ Not cached: the task read and wrote 'packages/rw-pkg/src/data.txt'
  If this file is temporary or shouldn't affect caching, exclude it (or a glob matching it) in the task's `cache` config:
    input: [{ auto: true }, "!src/data.txt"],
    output: [{ auto: true }, "!src/data.txt"],

• Both entries keep { auto: true }, because a list of exclusions on its own turns off automatic tracking. This is always safe here: the warning only appears when both lists track automatically.
• A file inside the task's package gets a package-relative pattern. A file outside it gets { pattern: "!…", base: "workspace" }.
• A task that opens a directory for both reading and writing (e.g. Linux O_TMPFILE) reads and writes the directory's path. For the workspace root that path is empty, and an empty pattern resolves to **, so no exclusion is shown. The package directory itself gets the base: "workspace" form.
• The path is glob-escaped with wax::escape and quoted with serde_json, so it is a valid string literal.
• The compact vp run: line is unchanged.
• docs/inputs.md gains a section on tasks that modify files they read.

The saved last-summary.json changes shape. A summary saved by an older version shows the existing "saved by a different version" message.

🤖 Generated with Claude Code

[github-actions]

fspy benchmark

linux

dynamic/launch             change  -1.00%  [ -7.71% ..  +7.26%]  overhead  +274.56%
dynamic/access             change  -0.01%  [ -3.68% ..  +2.35%]  overhead   +14.25%
dynamic/access-relative    change  +0.21%  [ -8.66% ..  +8.22%]  overhead   +61.38%
dynamic/access-contended   change  +2.12%  [ -5.56% .. +48.50%]  overhead   +20.95%
static/launch              change  +0.86%  [ -6.67% ..  +8.77%]  overhead  +716.07%
static/access              change  +0.03%  [ -4.71% ..  +6.87%]  overhead  +713.42%
static/access-relative     change  +1.38%  [ -3.09% ..  +8.13%]  overhead +1217.39%
static/access-contended    change  +1.90%  [ -1.36% .. +12.01%]  overhead +3107.03%

macos

dynamic/launch             change  +0.12%  [ -4.58% ..  +5.28%]  overhead  +219.66%
dynamic/access             change  +1.41%  [ -5.39% ..  +7.74%]  overhead    +4.64%
dynamic/access-relative    change  -3.60%  [-39.40% ..  +7.96%]  overhead  +252.17%
dynamic/access-contended   change  +3.80%  [ -5.19% .. +62.35%]  overhead    +4.55%

windows

dynamic/launch             change  +0.98%  [-12.70% .. +15.50%]  overhead   +23.52%
dynamic/access             change  -0.87%  [-12.83% .. +13.55%]  overhead    +2.20%
dynamic/access-relative    change  +1.38%  [-10.58% .. +23.76%]  overhead    +3.68%
dynamic/access-contended   change  -0.43%  [-11.46% ..  +7.57%]  overhead    +1.07%