Closes #3145.

chm upgrade is a first-class alias of chm update (same --check / --version flags, same cli_run/update telemetry). Self-update now prints current -> target version, and checksum / permission / unsupported-target failures are explicit with a copy-pasteable fallback (scripts/install.sh or cargo install ch-monitor-cli --force). The command never invokes sudo.

Summary

Users say upgrade as often as update. The CLI, installer, and docs now treat them as one product without breaking chm update.

Changes

• chm upgrade and chm update share UpdateArgs (--check, --version) in rust/ch-monitor-cli/src/main.rs
• Self-update UX in src/update.rs: print chm vX -> tag before work; checksum / permission / unsupported-target errors include install.sh or cargo fallback; never a sudo command
• scripts/install.sh: missing/empty checksum is fatal (no silent unverified install); unwritable dir suggests CHM_INSTALL_DIR / cargo instead of a doomed temp-path sudo cp; mentions chm upgrade
• Docs kept in sync: rust/ch-monitor-cli/README.md, docs/content/guide/guides/diagnostics-cli.mdx, docs/knowledge/standalone-cli.md
• rust/Cargo.lock package version aligned to crate 0.1.1 (no version bump)

Left alone

• chm update kept as-is for existing scripts
• Telemetry stays ("cli_run", "update") for both commands; CHM_LICENSE_KEY honor-system ping unchanged
• No Homebrew / crates.io / DRM / new product features
• release-please configs and chm-v* release PRs not touched

Test plan

• cargo test --locked in rust/ch-monitor-cli — 39 passed (version parse, newest-tag pick, alias wiring, fallback copy-paste)
• cargo clippy --locked -- -D warnings clean
• cargo fmt --all -- --check clean
• chm --help lists both update and upgrade; chm upgrade --help exposes --check and --version
• bash -n scripts/install.sh
• pnpm run lint — not applicable (Rust CLI / docs / install script only)
• pnpm run build — not applicable
• pnpm run type-check:test — not applicable
• pnpm run test:unit — not applicable
• Docs updated in docs/content/
• docs/content/ai-agent.mdx — not applicable (no agent tools/skills/env vars)

Notes for reviewer

Unsupported-target errors point at cargo install (source build) rather than install.sh, which would also refuse that platform.

Co-Authored-By: duyetbot bot@duyet.net