chore: timeseries e2e test coverage

[briangregoryholmes]

Summary

Adds e2e test coverage for rendering of the primary timeseries line.

This PR follows up on the timezone-related fixes in:

• fix: time series chart labeling #8659 - Fixed time series chart labeling regression

Changes

E2E Tests

• Adds tests to verify correct point and annotation placement on timeseries charts
• Validates that timezone handling works correctly across different dashboard configurations

Import Fixes

Fixed runtime-client imports across 27 files. The types were previously imported from a barrel file that also exports svelte-query related modules. Since svelte-query has Svelte dependencies that cannot be resolved in the Playwright test environment, the imports needed to be updated to reference the type definitions directly, bypassing the barrel file.

Checklist:

• Covered by tests
• Ran it and it works as intended
• Reviewed the diff before requesting a review
• Checked for unhandled edge cases
• Linked the issues it closes
• Checked if the docs need to be updated. If so, create a separate Linear DOCS issue
• Intend to cherry-pick into the release branch
• I'm proud of this work!