fix: clarify VS Code reload action

[BartWaardenburg]

Summary

• Switches the VS Code sidebar title action from search to refresh after analysis results have loaded.
• Keeps the initial run action as Fallow: Run Analysis with $(search), then shows hidden delegated Fallow: Reload Analysis with $(refresh) once fallow.hasAnalyzed is true.
• Adds manifest and integration coverage for the new command/menu wiring.

Issue

Closes #869

Plan

• Local plan: .plans/vscode-reload-icon.md

Verification

• npm run lint:js
• npm run fmt:js:check
• cd editors/vscode && pnpm run lint
• cd editors/vscode && pnpm run test
• cd editors/vscode && pnpm run check:codegen
• cargo check --workspace
• cargo test --workspace --all-targets
• cargo clippy --workspace --all-targets -- -D warnings
• cargo fmt --all -- --check
• cargo doc --workspace --no-deps --document-private-items
• git diff --check
• fallow audit --format json --quiet

Audit note: the complexity finding introduced by touching editors/vscode/src/extension.ts was fixed by simplifying the config-change callback. The remaining audit failure is unrelated to this diff: existing unused dependency findings in benchmark/reference package manifests (benchmarks/knip6/package.json, reference/knip/package.json, and related benchmark files).