feat: allow map_err like syntax on change_context

[khanhtranngoccva]

🌟 What is the purpose of this PR?

• Add Report::current_context_mut to access the internal error mutably. This is required if the caller needs to modify or extract non-Clone fields as part of error recovery.
• Add ResultExt::change_context_adaptive to allow map_err like syntax. This helps with cases of error propagation where the underlying error needs to be surfaced to the domain level in the current form or in another form.

🔍 What does this change?

• Added Report::current_context_mut
• Added ResultExt::change_context_adaptive

Pre-Merge Checklist 🚀

🚢 Has this modified a publishable library?

This PR:

• does not modify any publishable blocks or libraries, or modifications do not need publishing
• modifies an npm-publishable library and I have added a changeset file(s)
• modifies a Cargo-publishable library and I have amended the version
• modifies a Cargo-publishable library, but it is not yet ready to publish
• modifies a block that will need publishing via GitHub action once merged
• I am unsure / need advice

📜 Does this require a change to the docs?

The changes in this PR:

• are internal and do not require a docs change
• are in a state where docs changes are not yet required but will be
  • this is tracked in: Insert Link Here
• require changes to docs which are made as part of this PR
• require changes to docs which are not made in this PR
  • Provide more detail here
• I am unsure / need advice

🕸️ Does this require a change to the Turbo Graph?

The changes in this PR:

• do not affect the execution graph
• affected the execution graph, and the turbo.json's have been updated to reflect this
• I am unsure / need advice

⚠️ Known issues

• Compiler jank related to non-lexical lifetimes prevents embedding the report in case of a panic.

🐾 Next steps

• Re-introduce the report embedding in the unreachable! panic in Report::current_context_mut

🛡 What tests cover this?

• Test cases in test_change_context.rs and test_conversion.rs have been modified to cover these two functions.

❓ How to test this?

• Running cargo test is sufficient, as these tests are fuzzed.

[claude]

Claude Code Review

This pull request is from a fork — automated review is disabled. A repository maintainer can comment @claude review to run a one-time review.

[CLAassistant]

All committers have signed the CLA.

[cursor]

PR Summary

Low Risk
Small, additive public API on a published error-handling crate with focused tests; no auth or data-path changes.

Overview
Adds mutable access to the active error context and a Result extension for context changes that can read or modify the existing report before wrapping a new context—useful when fields are not Clone or need recovery (e.g. take() from the inner error).

Report::current_context_mut mirrors current_context via downcast_mut, with the same panic path if the typed context is missing (report text omitted in the panic message due to a known compiler limitation).

ResultExt::change_context_adaptive on Err builds the report, runs F: FnOnce(&mut Report<E::Context>) -> C, then applies change_context with the returned context—analogous to change_context_lazy but with access to the underlying report.

The crate is bumped to 0.8.1; tests use rand to assert preserved context values and resource extraction through the new APIs.

^{Reviewed by Cursor Bugbot for commit 47c732a. Bugbot is set up for automated code reviews on this repo. Configure here.}

[vercel]

@khanhtranngoccva is attempting to deploy a commit to the HASH Team on Vercel.

A member of the Team first needs to authorize it.