Add $tsIncrement compatibility tests

[RyanGarfinkel]

What does this PR do?

This PR introduces additional compatibility tests for the $tsIncrement operator. This includes null/missing values, invalid types, boundary values, and nested field access. Wiring tests were also added to verify functionality in $match, $expr, and $group expressions. An additional error code, TS_INCREMENT_TYPE_ERROR was added specifically for MongoDB type mismatches.

Why was this PR needed?

This PR Closes #210, which required adding additional test coverage to the $tsIncrement operator. Initially, this operator only had one smoke test, which tested basic functionality, not including null/missing input and invalid types.

What are the relevant issue numbers?

Closes #210

Does this PR meet the acceptance criteria?

• Tests added for new/changed behavior
• All tests passing
• Follows project style guide
• No breaking changes introduced (new tests added)
• Documentation updated (if applicable)

[documentdb-triage-tool]

🤖 Auto-triaged by documentdb-triage-tool.

Applied: compatibility test, enhancement
Project fields suggested: Component test-coverage · Priority P2 · Effort M · Status Needs Review
Confidence: 0.30 (deterministic)

Reasoning

component from path globs (test-coverage, test-framework); effort from diff stats (267+0 LOC, 4 files); LLM failed: Invalid response body while trying to fetch https://api.anthropic.com/v1/messages: Premature close

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