fix: precompile x-forwarded-host regexp

[ferhatelmas]

What kind of change does this PR introduce?

Bug fix

What is the current behavior?

In multitenant, if x-forwarded-host regex is given, it's compiled twice per request.

What is the new behavior?

Precompile it once and cache module level to cut down two compilation in hot path.

[Copilot]

Pull request overview

This PR reduces per-request overhead in multitenant mode by precompiling the configured X-Forwarded-Host regular expression once and reusing it, avoiding repeated RegExp construction in hot paths.

Changes:

• Introduces getXForwardedHostRegExp with a module-level cache keyed by the configured pattern string.
• Updates multitenant tenant-id extraction and tracing hooks to use the compiled RegExp instead of a pattern string.
• Adds unit tests to verify caching, recompilation on pattern changes, and behavior with invalid patterns.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/internal/monitoring/otel-tracing.ts	Uses a precompiled/cached RegExp for multitenant tenant extraction in incoming span hook.
src/internal/http/x-forwarded-host.ts	Adds helper to compile and cache the X-Forwarded-Host regex once per pattern value.
src/internal/http/x-forwarded-host.test.ts	Adds tests covering cache reuse, recompilation, and invalid-pattern behavior.
src/internal/http/index.ts	Re-exports the new x-forwarded-host module from the internal HTTP barrel.
src/internal/database/client.ts	Uses cached compiled RegExp for host checking instead of compiling per call.
src/http/plugins/tenant-id.ts	Uses precompiled/cached RegExp for tenant-id derivation from x-forwarded-host.

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[coveralls]

Coverage Report for CI Build 28780172781

Coverage increased (+0.01%) to 78.857%

Details

• Coverage increased (+0.01%) from the base build.
• Patch coverage: 2 uncovered changes across 1 file (20 of 22 lines covered, 90.91%).
• 3 coverage regressions across 1 file.

Uncovered Changes

File	Changed	Covered	%
src/internal/monitoring/otel-tracing.ts	3	1	33.33%
Total (4 files)	22	20	90.91%

Coverage Regressions

3 previously-covered lines in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
src/storage/protocols/tus/s3-locker.ts	3	78.37%

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Coverage Stats

Relevant Lines:	12249
Covered Lines:	10102
Line Coverage:	82.47%
Relevant Branches:	7043
Covered Branches:	5111
Branch Coverage:	72.57%
Branches in Coverage %:	Yes
Coverage Strength:	420.82 hits per line

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💛 - Coveralls