[m1ngshum]

The README had grown to 794 lines / 7,614 words, mixing onboarding with command reference, security internals and release history. Reduce it to 241 lines / 1,627 words, add a task-oriented docs index, and preserve useful detail in focused trust and usage guides.

Correct the documentation findings from Astra's repository review: scope confinement and TOFU claims; explain default-policy fallback; reconcile shipped VS Code scope and the metadata-only 0.52.1 checkpoint; correct warning flow, removed starter packs, CI/release guidance and signature coverage; clearly label historical plans. Compare the stdio relay, opt-in OS confinement and agent lifecycle hooks with their distinct coverage, failure modes and bounded experimental evidence.

Sol implemented the documentation changes; Astra independently reviewed and fixed the final patch. Documentation only: runtime, dependencies, workflows, public usage skill and the preserved historical archive are unchanged. No merge or release is included.

Validation at 5d0d5dacbc0f7af62f1a4aacd5e7b7c7d41c21eb: current-source command/claim checks, a before-fail/after-pass command-table structure check (42 rows), 271 local references across 63 Markdown files with no new missing file/heading targets, all 23 signature-catalog IDs, and git diff --check. The intentionally preserved historical archive's known relative link remains. Local runtime/native tests and historical measurements were not rerun; external links were not exhaustively revalidated.