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Closes #452

Adds tenant-scoped Windows/Linux software inventory from native clients through durable backend storage, client and estate views, and the shared HTTP/stdio MCP surface. Agents scan on their first authenticated connection, receive the enabled seven-day tenant default, and retain compressed chunk uploads until matching acknowledgements. Complete scans reconcile installations and changes atomically; partial, duplicate and superseded submissions cannot remove the last complete inventory.

Adds tenant policy settings beside Auto Update, a full-screen client dialog with the 30-minute cache rule and explicit refresh, searchable and sortable server-paged installations, prevalence with distinct device counts, change history, filtered CSV export, audit events, and selective Web proxy routes. netratel_software and SoftwareInventoryClient use the existing delegated managed-operation authorization; MCP reads remain inert and refresh requires explicit confirmation.

Validation:

• Debug application/test compilation; product version authority verified across all 22 projects.
• 51 focused Core/API/PostgreSQL/MCP/proxy tests passed (18.2s), including migration, concurrent refresh, tenant isolation, chunk reordering/replay, partial scans, large inventories, and outbox replay after restart, and byte-bounded Unicode metadata packing.
• All 8 historical PostgreSQL upgrade/rollback regressions and 5 production OpenAPI/authorization regressions passed.
• All 525 MCP regressions passed (29.4s), including transport isolation and real stdio process discovery.
• All 667 UI component regressions passed (80s), including cache behavior, forced refresh, tenant-switch response fencing and the existing tenant update-policy controls.
• All 177 source/release contract tests passed (124s); documentation/layout, PostgreSQL-only configuration, and public disclosure checks passed.
• Required GitHub validation passed: https://github.com/BostonTechnologies/netratel/actions/runs/41198118170 — 5,424/5,424 tests passed (4,721 Core, 36 API integration, 667 UI), with zero skips. The .NET job finished in 18m27s: restore 22s, build 2m58s, regression execution 14m15s, within the 20-minute budget.

Native Windows and distribution-specific collector execution, deployment smoke, and published-artifact functional acceptance remain owner checks, documented in docs/client/software-inventory.md. This PR does not publish a release; beta source preparation and promotion follow review and successful CI.