fix: distinguish bundle downloads from updates

[Brian Krabach (bkrabach)]

Summary

• Distinguish bundle downloads, updates, refresh-cache actions, unchecked sources, pinned sources, and local changes in amplifier update reporting.
• Keep aggregate mixed states and failure labels truthful, including completion verbs.
• Add a short reporting convention and real Click-command regression coverage for the nine-source download scenario.

Verification

• Full offline suite in the isolated target environment: 2067 passed, 3 skipped, 13 deselected, 1 xfailed in 20.65s.
• Independent focused review: 60 tests passed.
• Regression tests exercise the real Click command while mocking only external status/apply boundaries.
• One initial environment-sensitive truststore check failed in an unisolated local run; a clean-environment rerun passed without source or package changes. This change does not alter truststore behavior.
• No live reset, network update, LLM, or DTU run was used for this fix.

Scope

• Reporting-only CLI change. Bundle discovery/inventory, startup, action selection, force handling, and exit semantics are unchanged.
• CI expected: six unit-matrix jobs, two POSIX integration jobs, and the repository CLA check.
• No breaking changes.