Navigation/usability quick wins

[gjong]

Labels: enhancement, navigation, priority:P1
Parent issue: Epic: Documentation site overhaul

Problem
Several small Hinode/Hugo config toggles that would meaningfully improve usability are currently off.

Note: "Edit this page on GitHub" is already live — no action needed there.

Suggested fix

• Set navigation.breadcrumb = true in params.toml.
• Enable the search modal: navigation.search.modal = true.
• Set enableGitInfo = true in hugo.toml.
• Change pages.docs.metadata from "none" to show last-updated dates.

Acceptance criteria

• Breadcrumbs visible on all content pages.
• Search modal accessible from header.
• Last-modified dates visible on content pages.