release: prepare Command Center 1.5.0

[jonts-ai]

Summary

Prepare Command Center 1.5.0, paired with independently versioned Spacesuit 0.4.0 through existing v1 snapshot contracts. This PR does not tag, publish or enable optional integrations.

• Align package, lockfile and skill metadata; add scoped release notes and compatibility/publication guidance.
• Replace direct-to-main version/tag/publish automation with non-publishing validation and committed, tracked-file artifact staging.
• Test SemVer prerelease acceptance, metadata mismatch rejection, local-data exclusion, clean-tree requirements and unchanged Git refs.
• Rebuild the runtime bundle from locked dependencies.

Validation

• 299 tests pass both in the checkout and exported artifact; build, lint (existing warnings only), formatting and whitespace checks pass.
• Staged artifacts contain only committed allowlisted files; no registry upload was performed.
• A text-extension-filtered package copy with executable bits removed starts successfully; synthetic session explorer browser smoke passes without JavaScript errors.
• Companion work-graph compiler output passes the dashboard validator.
• Disposable 1.4.1 → 1.5.0 → 1.4.1 startup/rollback preserves custom configuration, privacy settings and workspace instructions.

Release boundaries

• Actual registry upload/download verification remains a publication gate.
• Operations browsing remains a bounded snapshot, not a server-paginated semantic graph or live tracker collector.
• Summary backend failures are not fixed by this version bump; metadata inspection remains independently usable.
• feat: add read-only session explorer with scoped grouping #76 remains open and is not included. This release uses the merged operations explorer.
• Stable publication is a separate explicit action after review/merge; -rc.1 is valid but optional SemVer.

Co-authored-by: Jonathan Tsai jontsai@users.noreply.github.com

[jontsai]

LGTM