fix(locations): preserve address edit authority and disclosure marker

[stef-k]

Saving an unchanged provider publication could falsely report an address conflict because hidden timestamp formatting dropped fractional seconds. Preserve round-trip precision and retain the original publication authority alongside submitted values during invalid-form redisplay, so corrected stale submissions still cannot overwrite newer enrichment.

Restore the native Address details disclosure marker by moving flex layout inside the summary. Includes an Unreleased changelog entry. Closes #565. Issue #566 is outside scope. No database migrations.

Validation:

• Independent review: READY FOR PR at 7c3308a; no reachable blocking defects.
• Reviewer freshly ran 13 focused tests, including PostgreSQL stale-publication and fresh-context persistence checks; build and diff checks passed.
• Actual InputTagHelper/MVC binding, null timestamps, one-microsecond publication changes, and realistic invalid/corrected submissions covered.
• Code Guard covered all six files. Accepted REVIEW: 844-line chronological changelog; no FAIL or INCOMPLETE.
• Historical red checkpoint is preserved, but no retained red-run output was found; historical execution is unverified.
• Browser validation debt: production marker states, pointer/keyboard activation, focus, narrow-screen wrapping, and screenshot remain unobserved. Host startup and a narrower retry were reportedly rejected by automatic approval review as blocked by policy. Independent review judged this nonblocking for restoration of native semantics; no screenshot is available.

GitHub Actions test on the exact PR head must succeed before merge.