CmdPal: Upgrade FuzzyStringMatcher in the Command Palette Extensions SDK (#44809)

## Summary of the Pull Request

This PR upgrades the `FuzzyStringMatcher` used in the Command Palette
Extensions SDK with a focus on performance, memory efficiency, and
improved matching behavior, while preserving compatibility with the
existing API. This PR is a backwards compatible alternative to
precomputed fuzzy matcher introduces in another PR.

The new implementation is designed as a drop-in replacement. Any
behavioral differences are intentional and primarily related to improved
diacritic handling, scoring consistency, and correctness of highlight
positions.

Changes:
- Keeps the existing public API intact and preserves behavior in nearly
all cases.
- Enables diacritics-insensitive matching by default, improving results
across accented and non-English languages.
- Significantly improves performance, with measured speedups in the
range of ~5–20 times, depending on scenario and input size.
- Reduces heap allocations to near zero by using stack allocation and
pooled buffers instead of large per-match DP arrays.
- Simplifies and optimizes matching logic:
  - Folds the haystack only once per match.
  - Uses rolling DP buffers instead of `O(query × target)` tables.
- Replaces large match tables with a compact bitset when tracking
highlight positions.
- Improves consistency and correctness:
  - Normalizes path separators (`\` → `/`) during folding.
- Avoids returning highlight positions for PinYin-only matches where no
1:1 mapping exists.
- Introduces unit tests, including comparison tests against the legacy
implementation to validate compatibility.

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## PR Checklist

- [x] Closes: #44066
<!-- - [ ] Closes: #yyy (add separate lines for additional resolved
issues) -->
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

src/modules/cmdpal/extensionsdk/Microsoft.CommandPalette.Extensions.Toolkit/Microsoft.CommandPalette.Extensions.Toolkit.csproj

@@ -56,7 +56,7 @@
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     </None>
    </ItemGroup>
-    
+
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@@ -83,4 +83,8 @@
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     <WarningsNotAsErrors>IL2081;$(WarningsNotAsErrors)</WarningsNotAsErrors>
   </PropertyGroup>
+
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 </Project>