Offer the Bridge plugin where an operator actually looks (#118)

[CaYatur]

Offer the Bridge plugin where an operator actually looks (#118)

On a Paper server with no bridge jar, neither the app nor the panel offered to
install one. The offer existed — in the live map's empty state, which turns out
to be the one place it cannot do its job.

That state renders only when there are no players to draw. A server with
people on it and no bridge showed an empty-looking map, no explanation and no
button, because mapDraw returns before the empty state on any frame with
markers. It also required opening the map tab at all: bridgeStatus was fetched
by mapStart() and nowhere else, so an operator who never went there was never
told that half the features were switched off for want of a 6 KB jar.

The desktop gets a BridgeNotice component, shown above the live map and in
the Plugins/Mods view — it is a plugin, and a missing plugin belongs in the list
of plugins. The panel gets the same banner outside the tab panels entirely, so
it is visible on console, stats, timeline or anywhere else, fetched once when a
server is opened rather than once per map visit.

It also says what the jar unlocks. "Install MSMS-Bridge" is not a reason to
click anything; "true TPS, live positions and the world map need this, and it
reports over the server console so no extra port is opened" is.

The map's empty state keeps only the part that is genuinely about the map — why
the canvas is blank, and the note that this server type cannot run the plugin at
all.

Asserted on the case the old placement could not reach: a supported server with
a jar available renders the banner, it says both what is missing and why it
matters, and every state nobody can act on — current, unsupported, or missing
with nothing to install — renders nothing, because a permanent banner is noise.

[Copilot]

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[CaYatur]

Self-review: put the banner in one place, and don't carry a result between servers

I placed the panel notice among the tab panels. Those are siblings, so it
rendered below the console on the console tab and at the top on every other one
— a banner that moves depending on where you are is worse than one that is
always in the same place. It sits above the tabs now, next to the server header
it belongs to.

The install result also outlived its server: switching servers left "Installed
1.0.0. Restart the server to load it." sitting under the new server's notice,
attributing one server's outcome to another. loadBridgeNotice clears it, and the
install path writes the message after that call rather than before.