refactor(language_server): introduce helper path_to_uri

[Sysix]

Currently only used for the test. The plan is to convert paths back to URI when we implement workspace wide diagnostics.
The client will not send us URIs, we need to create them on our own.

The current implementation from Uri::from_file_path is broken because of the escape characters.
I see someone from tower-lsp-server wants to implement something similar:
tower-lsp-community/tower-lsp-server#46

[Sysix]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• feat(language_server): support workspace/diagnostic #11414
• feat(language_server): support textDocument/diagnostic #11447
• refactor(language_server): linter runtime returns FxHashMap #11412
• refactor(language_server): introduce helper path_to_uri #11398 👈 (View in Graphite)
• refactor(linter): move Walk from oxlint to oxc_linter with own options struct #11391
• main

---

How to use the Graphite Merge Queue

Add either label to this PR to merge it via the merge queue:

• 0-merge - adds this PR to the back of the merge queue
• hotfix - for urgent hot fixes, skip the queue and merge this PR next

You must have a Graphite account in order to use the merge queue. Sign up using this link.

An organization admin has enabled the Graphite Merge Queue in this repository.

Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #11398 will not alter performance

_{Comparing 05-30-refactor_language_server_introduce_helper_path_to_uri_ (9f39a1d) with 05-30-reactor_linter_move_walk_from_oxlint_to_oxc_linter_with_own_options_struct (bbf7107)}

Summary

✅ 38 untouched benchmarks