[dragonked2]

The v1.0.92 commit failed compilation in CI, release, and Alpine builds with five errors: references to an uncommitted session-copy module, state, and protocol event, plus a missing Mermaid capability re-export.

Remove the orphaned session-copy handlers; the released protocol has no corresponding request or response. Re-export the existing native-image capability function used by the plan-graph gate.

Plan-graph test fixtures explicitly select native image support on their own test threads. The empty-plan regression scopes both renderer and protocol overrides, avoiding dependence on headless runner capabilities or process-global picker initialization order.

Validation:

• Formatting and diff whitespace checks passed.
• Workspace check and test-compilation check passed with the locked dependency graph.
• Clippy passed with warnings treated as errors.
• Local library suite: 6,412 passed, 11 ignored, zero failures (unoptimized test executable; normal color terminal environment).
• GitHub CI release builds passed on Ubuntu, Windows, and macOS.
• CodeQL and installer smoke checks passed.