[sainadh777]

Summary

• add a Manager session-detail action and form for updating a primary session's maximum inactive interval
• validate the submitted interval and handle sessions that disappear or become invalid during the update
• replace the corresponding TODO and add focused integration coverage and a changelog entry

Rationale and impact

The session detail page displayed the maximum inactive interval but left updating it as an unfinished TODO. This completes that workflow through the existing CSRF-protected Manager HTML endpoint. The change is limited to the Manager web application and does not alter container defaults or session behavior outside an explicit administrator update.

Validation

• ant validate validate-eoln — passed
• ant -Dtest.entry=org.apache.catalina.manager.TestManagerWebapp test — 5 tests, 0 failures, 0 errors, 0 skipped
• ant clean deploy — passed
• ant clean test — 42,084 tests, 0 failures, 0 errors, 364 environment-declared skips
• packaged runtime smoke — Tomcat started, GET / returned HTTP 200, and Tomcat stopped cleanly

The complete suite and runtime smoke ran with Eclipse Temurin JDK 25 on a native Linux case-sensitive Docker volume.

[sainadh777]

@markt-asf @rmaucher — would you please review the Manager session-timeout UI and action? You both recently changed the same Manager session code and tests.

[markt-asf]

No objections to the general direction of this PR. I do have a few questions on the test changes.