chore(dsh): move plugin to integrations repository

[Yangtze-Seventh]

Summary

• remove the duplicated examples/dsh integration, its dedicated CI workflow, and its Dependabot entry from the EverOS core repository
• keep all generic EverOS support introduced with the original integration, including defer_extraction, API contracts, service behavior, documentation, and tests
• leave examples/langfuse and every other example unchanged
• leave GitHub repository topics unchanged

The complete DSH plugin has moved to EverMind-AI/plugins in EverMind-AI/plugins#7. Merge that PR before this cleanup to avoid a temporary discoverability gap.

Scope

This removes the 22 tracked files under examples/dsh, .github/workflows/dsh.yml, and only the DSH npm block in .github/dependabot.yml. Equivalent CI and dependency-update coverage now live in the integrations repository. There are no changes to EverOS source code, Python dependencies, public APIs, shared CI jobs, or other examples.

Verification

• confirmed the migrated DSH source, tests, lockfile, and Cordis patch match the former EverOS implementation
• 37 passed across the memorize integration tests, API request validation tests, and memory span tests
• git diff --check passed
• repository-wide search found no remaining examples/dsh, @evermind-ai/dsh-plugin, or DeepSeek Harness references outside the removed directory

Existing baseline

A repository-wide Ruff run still reports six unrelated findings already present on main in benchmark, e2e, and OpenHER files. This PR does not touch those files.