feat(P02): install.sh 1-liner + in-place update + README quickstart
REQ-043: install.sh pulls release binary from public Gitea URL.
User-level default (~/.local/bin/orca), --system for system-level
(/usr/local/bin/orca). Defaults to latest release; --version pins.
Env-overridable GITEA_URL/OWNER/REPO for testability.
REQ-044: in-place update detects existing binary, reads version via
'orca version --json', prints update message, overwrites binary,
preserves namespace dir (config/db/certs). Idempotent re-install.
REQ-016 (completion): README quickstart now documents the 1-liner
install + --system variant + update-in-place pattern.
Tests: 8/8 pass in scripts/install_test.sh (real public Gitea releases,
no mock server; timeout-guarded to prevent hangs).
Docs: docs/install.md covers user/system install, version pinning,
in-place update, uninstall, troubleshooting.
---ci---
project: orca
phase: 2
milestone: v0.5
status: verify
---/ci---
Jon Chery
85963dc320