chore: temporarily suspend Flashgrep distribution and UI entries

[wgqqqqq]

Summary

Temporarily suspend Flashgrep distribution and hide its frontend entry points. Remove all six bundled platform binaries, the accelerated-search settings switch, index status/rebuild entry points, and related global-search controls. The frontend also stops index requests when an existing installation has the saved preference enabled.

Type and Areas

Type: maintenance / UI

Areas: Web UI, desktop development and packaging, Windows installer

Motivation / Impact

Flashgrep is temporarily unavailable in this release. Development and packaging no longer require the removed binary, and Windows installer payload validators no longer reject packages without it. Existing preferences, backend implementations, and shared host contracts remain intact for compatibility and later restoration.

Verification

Passed locally on macOS:

• node --test scripts/desktop-tauri-build.test.mjs scripts/prepare-dsh-profile.test.mjs OpenBitFun-Installer/scripts/build-installer.test.cjs — 32 tests passed.
• pnpm --dir src/web-ui exec vitest run src/app/global-search/providers/interactiveCapabilitySearchProvider.test.ts src/tools/file-explorer/search/useWorkspaceSearchIndex.test.ts — 14 tests passed, including suppressed index requests with an enabled preference and packaging without Flashgrep covered by the script suite.
• pnpm run check:web
• pnpm --dir OpenBitFun-Installer run type-check
• cargo check --manifest-path OpenBitFun-Installer/src-tauri/Cargo.toml
• pnpm run fmt:rs and git diff --check for the submitted changes.

Full desktop/Windows installer packaging and visual UI verification were not run. No remote-workspace, remote-control, Peer Device Mode, or Detached Dispatch end-to-end scenario was exercised; the hook tests mock the API and are not evidence of remote runtime behavior.

Reviewer Notes

AI-assisted implementation; verification level: lightly tested (focused tests and static/compile checks). This is a distribution and frontend suspension, not removal of backend search APIs or persisted data. Restoration guidance is retained in resources/flashgrep/README.md.

Checklist

• This PR is focused and does not include secrets, temporary prompts, generated scratch files, or unrelated artifacts.
• Relevant verification is recorded above, or skipped checks are explained.
• User-facing strings, docs, and locales are updated where applicable.