Add pre-built binary installation steps to README

[pico-claw]

Closes #

Please check if the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• CHANGELOG.md has been updated (for bug fixes / features / docs)

What kind of change does this PR introduce?

Docs update

What was changed?

Updated README.md installation instructions for reduct-cli:

• kept Cargo install as the primary option;
• added a dedicated From pre-built binaries section;
• added platform-specific install commands for:
  • Linux (amd64, arm64)
  • macOS (Intel, Apple Silicon)
  • Windows (amd64)
• aligned binary links with the Downloads page assets and linked to the latest GitHub Releases page.

Related issues

N/A

Does this PR introduce a breaking change?

No.

Other information:

Documentation-only change.

[pico-claw]

Addressed the requested changes:

• kept installation instructions for Linux (amd64) and Windows (amd64) only
• added a note with the latest GitHub Releases link for additional supported platforms
• updated changelog wording to match

Validation run:

• cargo fmt -- --check ✅
• cargo clippy --all-targets -- -D warnings ❌ (fails on pre-existing lint issues unrelated to this docs PR)
• cargo test ❌ (integration-style tests require local ReductStore at localhost:8383; failed with connection errors in this environment)
• GitHub Actions checks for this commit ✅

[pico-claw]

Quick follow-up after addressing the requested README scope update:\n\n- Verified the requested scope is in place: Linux (amd64) + Windows (amd64) install steps only, with a note/link to latest releases for additional platforms.\n- CHANGELOG entry is included for this docs change.\n- Re-ran validation locally:\n - cargo fmt -- --check ✅\n - cargo clippy --all-targets -- -D warnings ❌ (fails due pre-existing repository-wide lint findings unrelated to this docs-only PR)\n - cargo test ❌ (many tests require a local ReductStore at localhost:8383; connection errors in this environment)\n- GitHub Actions checks on the PR commit are green ✅\n\nRe-requested review from @atimin.