Use canonical memory allocation dependency in 0.3.x

[coenttb]

Summary

• replace the redirecting personal dependency URL with the live Institute-owned repository URL
• update the SwiftPM package identity to match the canonical repository name
• preserve the TestingPerformance product, source, behavior, and from: "0.2.0" requirement

Related to #8. This PR does not close the issue because a compatible tag remains separately gated and unauthorized.

Composition evidence

• both the old and canonical URLs expose 0.2.0 at commit afe7e86f16981007b841470d5ea79f0026868bc3
• that tagged manifest exports the required MemoryAllocation product
• Workspace resolution selects swift-memory-allocation-primitives 0.2.0 from the canonical .git URL and records no github.com/coenttb/* location

Verification

• workspace package resolve: passed
• workspace package build --fresh: passed on Swift 6.4
• workspace package dump-package: preserves TestingPerformance and the 0.2.0..<1.0.0 requirement
• workspace package test --fresh: all 130 tests built and ran; the unchanged wall-clock test fast operation threshold fails on this machine at about 151 µs against its fixed 100 µs threshold

The diff contains no source or test changes. Full off-machine CI is dispatched separately before merge.

[coenttb]

Full off-machine CI passed at head f68c3752e20a6d438fbe309ef8fd45ccbf4a186a: run 30470633320 is green on macOS Swift 6.2 debug, Ubuntu Swift 6.2 release, Ubuntu Swift 6.2 compatibility, and Windows Swift 6.2 release. Every leg built and tested successfully; macOS also validated the manifest and API. The local Swift 6.4 wall-clock threshold failure did not reproduce on the supported off-machine matrix.