Unify Dashboard and System tab hero panels; move version/database/IP metadata to Administration

ROADMAP.md

@@ -194,3 +194,5 @@ Roughly in priority order:
 `v0.16.33` fixes the System tab hero panel's Network stat printing absurd, layout-breaking values like "846.7603211009175 B/s" instead of a clean rounded number. Root cause: `formatBytes()` only rounds once a value crosses into KB -- below 1024 it returns the number exactly as given, which has always been fine because every other caller passes it a file size (always a whole integer). The Network stat is the first caller to feed it a computed rate (bytes divided by elapsed seconds), which is almost never a whole number, so sub-1 KB/s readings rendered with a dozen decimal places and wrapped onto a second line, breaking the hero panel's layout. `formatRate()` now rounds to the nearest whole byte before handing off to `formatBytes()`, matching what every other value passing through it already looks like.
 
 `v0.16.34` fixes the System tab hero panel's helper text not lining up across columns -- Network and Throughput don't have a meaningful usage bar (neither is a percentage of anything), so that bar was hidden with `display:none`, which removes it from the flex layout entirely rather than just hiding it. The other four columns (CPU, Memory, Swap, Disk) still have their bar taking up space between the value and the detail line, so Network and Throughput's detail text sat visibly higher than everyone else's, breaking the row's shared baseline. Switched to `visibility:hidden`, which keeps the bar's space reserved without drawing it, so all six columns now keep identical vertical rhythm and every detail line lands on the same line.
+
+`v0.16.35` unifies the Dashboard's Runtime/System panel with the Administration > System tab's hero panel instead of the two showing different, disagreeing numbers for the same underlying stats. The Dashboard's Memory tile used to read `process.memoryUsage().rss` -- the Node process's own footprint, not the container's real usage -- while the System tab's hero (added in v0.16.29-34) correctly read cgroup v2's `memory.current`. There was no CPU stat on the Dashboard at all, and "Site Gateway data" plus "Storage available" were two separate numbers where the System tab's Disk stat already combined them into one coherent, `DATA_DIR_LIMIT_GB`-aware percentage. Rather than keep two implementations in sync by hand, the Dashboard's panel is now the exact same hero component -- same markup builder, same `renderHeroPanel()` function, same `/api/system/health` endpoint, same polling-while-visible pattern -- so the two can't disagree again, because there's only one implementation computing the numbers. The Dashboard's copy shows CPU, Memory, Swap, Disk, Network, and Uptime; Throughput is left out there since the Dashboard already has its own "requests / min" chip in its metric strip and showing the same number twice added nothing. Uptime keeps ticking client-side exactly as it did before (same `updateDashboardUptime()` timer, just now living inside the hero's sixth slot instead of a standalone tile). Everything else that used to live in that panel -- Site Gateway version, Caddy version, Database status, and Public IP -- moved to the Administration > System tab's existing Version panel, alongside the Site Gateway version and access-URL details already shown there, so nothing was lost, it just now lives with the rest of the deployment's operational metadata instead of being split across two pages. The Dashboard's hero grid also gets its own CSS breakpoint (3 columns by default, 2 below 900px) rather than reusing the System tab's viewport-keyed breakpoints, since it sits inside the Dashboard's half-width two-column layout rather than a full-width panel and would otherwise stay cramped at 6 columns on an ordinary desktop window.