test(tree): cover divergent optional field compatibility

[Alex Villarreal (alexvy86)]

Description

Adds a unit test covering TreeView compatibility when two schemas share the same node identifier and allow unknown optional fields, but independently add different optional fields.

The test creates one document with fieldA and another with fieldB, then opens each document using the other view schema. It documents that both cross-open scenarios are incompatible: canView, canUpgrade, and isEquivalent are false, and accessing the root throws a compatibility error.

Reviewer Guidance

The review process is outlined in the pull request guidelines.

Please confirm that the asserted incompatibility is the intended behavior for divergent optional fields when allowUnknownOptionalFields is enabled.

[github-actions]

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[github-actions]

Bundle size comparison

Base commit: 433c666b69b016be388aed1471273559109c8e41
Head commit: e6af164d81ae1f295b90c1e7f7d892a2e18a08d3

Notable changes

No bundles changed by ≥ 500 bytes parsed.

Per-bundle deltas

@fluid-example/bundle-size-tests

• fluidFrameworkAllAlpha.js: parsed 803433 → 803489 (+56), gzip 220814 → 220893 (+79)
• azureClient.js: parsed 633816 → 633811 (-5), gzip 169820 → 169911 (+91)
• odspClient.js: parsed 605062 → 605173 (+111), gzip 162623 → 162771 (+148)
• aqueduct.js: parsed 537741 → 537752 (+11), gzip 144457 → 144504 (+47)
• fluidFramework.js: parsed 413384 → 413417 (+33), gzip 117282 → 117275 (-7)
• sharedTree.js: parsed 402763 → 402789 (+26), gzip 114709 → 114713 (+4)
• containerRuntime.js: parsed 314508 → 314490 (-18), gzip 86288 → 86290 (+2)
• sharedString.js: parsed 175239 → 175246 (+7), gzip 49670 → 49677 (+7)
• experimentalSharedTree.js: parsed 161846 → 161846 (0), gzip 46722 → 46722 (0)
• matrix.js: parsed 159618 → 159625 (+7), gzip 45914 → 45921 (+7)
• loader.js: parsed 147327 → 147343 (+16), gzip 40038 → 40048 (+10)
• odspDriver.js: parsed 105689 → 105747 (+58), gzip 32933 → 33000 (+67)
• directory.js: parsed 65669 → 65676 (+7), gzip 18493 → 18500 (+7)
• 578.js: parsed 58686 → 58686 (0), gzip 17657 → 17657 (0)
• odspPrefetchSnapshot.js: parsed 45921 → 45902 (-19), gzip 15347 → 15357 (+10)
• map.js: parsed 45820 → 45827 (+7), gzip 14119 → 14126 (+7)
• 252.js: parsed 44384 → 44384 (0), gzip 13741 → 13741 (0)
• summarizerDelayLoadedModule.js: parsed 31287 → 31287 (0), gzip 7929 → 7929 (0)
• socketModule.js: parsed 26992 → 26962 (-30), gzip 8019 → 8053 (+34)
• createNewModule.js: parsed 12464 → 12464 (0), gzip 4792 → 4805 (+13)
• summaryModule.js: parsed 3888 → 3888 (0), gzip 1874 → 1874 (0)
• connectionState.js: parsed 909 → 909 (0), gzip 500 → 500 (0)
• sharedTreeAttributes.js: parsed 845 → 852 (+7), gzip 493 → 504 (+11)
• debugAssert.js: parsed 429 → 429 (0), gzip 299 → 299 (0)
• FluidFramework-HashFallback.js: parsed 419 → 419 (0), gzip 313 → 313 (0)